I'm really new to game development, I've messed around with stuff here and there but I've never gone and released anything yet. I thought this might be a decent starting point, and I like the Game Boy, so it sounds nice. Also, I just wanna finally get into game dev, I've been pushing it off for too long. Only issue is, I'm pretty much a beginner so I feel completely lost lol. I have most of my experience in art, and I have some beginner level experience in coding in Unity and making music. I was wondering if anyone here had any advice and stuff, I'll take anything. I don't have any specific questions unfortunately, sorry about that. I was just feelin a little lost and wondered if I could gather at least a bit of info here.

Sorry if this isn't the place to post this, I can always delete it if ya need me to. I hope you're all having a good day though. Best of luck to ya.

Commit to it

If you're going to do a game jam, make sure your schedule isn't busy. When the theme is revealed, start thinking about ideas and make sure to write them down somewhere to not forget.

Games don't have to be perfect

Games here are prototypes and don't have to be fully fleshed out. Make anything (as long as it corresponds with the theme and rules) you want and release it!

Take breaks and stay hydrated

It's easy to get lost on your project so it's a good idea to add reminders to take breaks at some point. Stand up, stretch,  go outside for a walk to clear your mind, and stay hydrated.

Have fun

Games jams are all about having fun and making something you enjoy. When you release your game, you'll feel proud on what you created and that will motivate you to participate in more jams!

@not_davido makes some good points: here are some more.

Don't be afraid
Your first game may be broken, not what you intended and will have a lot of problems, but everyone must experience this in order to improve. Submit it anyway. It's good to make other people feel comfortable with posting unfinished WIP games.

Check out GBStudio
GBStudio has drag and drop code and an extensive amount of documentation and third party tutorials. It can also export ROM games to be played on original hardware.

Reduce your scope
Everyone wants to make the next big MMO game, but realistically even games like pong and space invaders can be a bit of a stretch. Think of an idea and cut it down and then cut it down some more. Even making a short interactive title screen is a valid entry.

Your game doesn't even have to be playable
You only have to convey your idea for the game. You can even make a series of screenshots or a music album and submit that.

Submit something at least 24 hours before the deadline
You never know when your code might go wrong or not render properly. Submit something, anything, before the deadline and then update with another file later.

Team up with others
Other people may be able to fill out the gaps in your knowledge. Peers and mentors are valuable for getting started in game development.

You've picked a great place to dip your toes in the water. Gameboy games are pretty basic in nature: you only have to worry about 4 colors, the art doesn't need to be highly detailed (and honestly, with few colors it can be messy if they are over detailed) and mechanics are usually simple. So don't try to over-complicate it.
If you're not too comfortable with coding and don't have someone to help you on this project, you could give something like GDevelop a go. It uses visual scripting, and you're able to set the screen resolution to that of a gameboy. There's templates available to help get you started and plenty of well-made tutorials.
Also, it's free and can export to web and desktop.

Most of all, have fun with it. Game jams are incredibly fun and you can learn a lot. It's also a great way to network with other people by collaborating.

Best of luck!

Ah thanks everyone! I really really appreciate all the tips and stuff, I'll make sure to keep em all in mind while working. Excited to try it out.

Best of luck.

Thank you!