Congrats on you launching your own business line and kudos to you wanting to improve on your skillset.
Firstly it is always at your advantage if you do something that you already know or have the passion for. By doing that you would already eliminate going into the business not have any of the know how except what you were taught. You would have already being practicing that business in an informal way but choosing to establish it would make you feel a lot more confident in yourself that you know the product you are offering . You are already sold on it.
Secondly:- It always help to invest in further training so that you can be competent in what you are offering. With global technology and cutting edge business modules and tools you really wants to be a cut above the rest and to offer the best you know how but in practical and theory. Ongoing training and development is a tool that you are going to be using not just for yourself, but as the business develops you would also need to in-cooperate that as tools for your employees as well
That being said you may choose to do courses either before or start the business and continue with courses that will matriculate you into the best you that will fit you for what you are offering..
There are many online courses of even face to face that you can apply to but ensure that the curriculum matches what you are looking for. Know your objectives and expectation and manage it throughout the course to ensure it is aligning to your business module.
When all is said and done, you can only be a better version of you by getting the knowledge you need. And even if you don't use it now, be assured that it will come in handy further on .
Best of wishes on both your decisions and do let me know the outcome