This is really a question for your attorney but a quick (layman's) answer is that today's copyright protections cover writers almost automatically once you complete and publish your works (research this online). Here is one source of info:

https://corporate.findlaw.com/intellectual-property/copyright-law.html

Trademarks are more related product and service names rather than content and must be applied for.

Sorry I can't be more comprehensive.

One thing I'm sure of is that you have to proactively defend your intellectual property rights. No one is going to do this for you. So if you see someone stealing your work it is your responsibility to notify or prosecute them.