I've been trying to launch my business for about a year now. I still have no idea whether this will work long term or whether I'll have to get a job, so I want to point out the following:
A year sounds like a lot now, but everything takes longer than you think it will. Clients need a string of well timed follow up calls before they buy anything, technical problems can get out of hand... you might even end up locked down in a worldwide pandemic!
I think it's quite likely you'll get to the end of your allotted year, and realise that you want to keep working on your project, and that you have the means to, but at the same time aren't at all sure if you've "made it" or not. You may decide that, even if you are probably going to quit, you should work for a bit longer so you at least have a finished product that you can show off to employers. You may even start job hunting after a year, but not get one straight away (not unlikely in a post-corona world...)
I think, most likely, you'll be like me -- you have a few encouraging little signs that you should keep going, and you'll really want to, but it's still entirely possible that you'll have to quit eventually. As such, my advice is:
Assume you will be doing this for more than one year! Set aside time to keep up skills that you won't develop on this project, even if it's ok not to work on them for one year; be careful with your money; be mentally prepared for setbacks!
I can't comment on how this will look to employers since I haven't yet gone back to work, but I imagine that the fact that you've tried your own business, and the time spent doing it, are less important than what you did and how you did it.
I wish you all the best, and I hope you have a lot of fun... just be ready for things to not go to plan ;)