How do I learn how to use it? I'm a beginner in Wordpress.
As I've been using Wordpress since before 2008, I have The Curse of Knowledge about this topic. That means I don't remember what it's like not to know anything about it. Wordpress seems simple and straightforward to me. I'm saying this so you understand where I'm coming from.
I've also never liked this phrase "best practices". It has no meaning to me--even as an Operations Management / process engineering guy--and seems like a cop-out where you want someone to spoonfeed the answers to you (I'm speaking in general here, not about you specifically).
The fact is, learning works this way:
You try something, and it doesn't work. Then you go dig for answers so that you understand the nature of the problem better...and the syntax for how to make the thing do what you want.
Syntax is the set of commands needed to produce the desired result. Calling your dog over has a syntax. Buying food at the grocery store has a syntax. And Wordpress has a syntax.
Most Wordpress problems are of syntax in nature: you know what you want it to do, but you're not sure how to get it to do that.
The basis of Wordpress is that it is a Content Management System (CMS) for posting material on the Internet. It looks an awful lot like MS Word, with a bunch of menus around the sides. Many of these menus you'll never or only rarely use.
Wordpress has a core. That's the base functionality you install, which is being hosted somewhere for you. That base functionality allows you to add Pages and Posts. Think of a page as a more permanent fixture you want people to see or be able to see all the time when they visit your site, and a post as a more temporary message like a blog post for today that may not have much relevance six months or a year from now.
You can add to this functionality with Plugins. Many plugins are useful, such as Wordfence (added security). Some are silly or highly specific in function and you may never need them. Only install and keep plugins you know you need, and that work (they can get outdated, or break) as each one bloats the size of your site.
The final main piece of Wordpress is the Theme you choose for the look and feel of your site. There are free themes and paid themes. Paid have more support and tend to be a bit more specific in their functions. Beware of Free...it can often mean that, yes, the basic setup is free...but if you want upgrades to 'free'-provided plugins later on, they'll want you to pay for them. Ignore that and you get left with an outdated plugin which may develop a security fault.
You may have several themes loaded into your Wordpress site, but only one can be used at a time. The rest sit in the background "turned off".
Choosing a theme, at least as far as I have found over the past nine years, can be one of the most lengthy time investments involved. I have learned to set a time limit--usually 2 or 4 hours--and after that stop looking. I limit myself to the theme options list I've developed so far, and choose one from that. Otherwise, the search for perfection could go on forever.
The putting up of words and images on your site should be easy for you if you are familiar with MS Word. Many themes give you 'drag and drop' functionality as well, though that can result in complications as you build extensive customized blocks of content on pages. It can get difficult to remember what is where behind these 'drag and drop' box covers.
Wordpress will scan itself and tell you when plugins or themes are out of date and need updating.
You may choose a theme, and discover it does not lead to conversions (turning visitors into buyers, if that is your goal). Designers create themes with a look and feel they like...but their creations do not always do anything but look pretty in the real world. If after six or 12 months your site is not doing what you want it to do, consider changing your theme to a radically different one.
As an example, my main corporate site in the early 2010s had a standard sort of look--hero banner image across the top, basic menu, landing page content below. This layout converted and brought me weekly leads.
In 2013 a web designer, yes, a web designer who we should understand has an agenda here, commented that it looked out of date. I trusted this designer as she worked in with attorneys and their websites, and was a sales training client of mine. I changed the site to a new (at the time) single page parallax style, which I call 'toilet paper roll' as it goes on and on and on. Guess what? Conversions stopped dead. I held onto the idea for a year.
In 2015 I converted the site to a magazine theme format, which it remains with today. Surprise, within a week the site started producing conversions again. How people interact with your content is important, and that is part of the Wordpress CMS.
Be clear what the purpose of your site is before you begin creating it.
I have, for instance, had sites that were not meant to convert--they were not meant to be encountered by people who had never heard of me before--but instead acted solely as supporting documentation to make the buyer feel good after our sales call.
My main site today is intended to get newbie visitors 'lost'...consuming content, going down rabbit holes and not leaving. Building authority. It works.
Other sites, like my blog, are more standard in nature: "Here is my thought on the topic; if you want more, there are tons of posts all around and easily accessible."
What will happen as you build and expand your site is that you will want to do something. But you'll realize you don't exactly know how to do it. Now we have returned to syntax.
At this point you know what words to Google or search for on YouTube to find that syntax. "hide user name wordpress security blog post", for example, could bring up a plugin like WP Author Slug, which replaces your user name at the end of a blog entry with a nickname. Why would this be important? Well, user name and password are the two things a hacker needs to log into your site as YOU, the administrator, and run amok. Half of that information is right there on the blog post. Oops.
Wordpress is not 'rocket science'. It is an easy CMS and you should be able to get a site up within a day. You can add to it as you go and learn what you need. As time goes on and your experience with it expands, you can increase your level of granularity and detail within its functions, such as by using a plugin like Simple Custom CSS to bypass the 'storefront' menus and themes of Wordpress to directly change the look and feel of the site.
I've been working with cameras since around 2004. In the past year I got back into digital photography. Here's the deal: I take a lot of pictures. I bought different lenses, and work with them every day to find out how they work with my camera. I'm about to go outside and try two new ones.
I didn't wait around for anyone to spoonfeed me: I went and got my own direct experience. And yes, I watch a ton of photography videos to supplement that direct experience, but they'd have far less impact and meaning without my own experience.
That's how I learn. This FD mount lens won't easily go into manual aperture mode? OK, I know to look that up on YouTube. I'll find videos showing me exactly how to do that. I'll get a screwdriver and try it myself, and now I know the syntax for that.
No different with Wordpress. My advice: Get Using It.