Idk how anyone with experience feels, but I think you should just go for it. Before like 2 months ago I hadn't written any fiction in about 2 decades (fuck i'm old), drawn anything in about the same amount of time, and knew barely anything about programming. I'd been contemplating making a game for years, but kept putting it off until I finally said, fuck it, and just jumped in.
Since then I've written a few fics, bought a cheap-ish art tablet to learn digital art (so many youtube videos), played around with renpy, and took a python class to learn the basics. I know myself though, if I try to wait until I'm satisfied with my skills I'll never actually finish anything, so I made myself join the jam to force myself to finish something. It might end up hot garbage, but at least I will have done it.
Whether you join a team or make something on your own I hope you decide to join the jam! I will look forward to playing whatever you make :)