Hey,
So last year I was in the same situation as you are now and I managed to make a browser game for the jam with Unreal. In short you can't use UE5, but you can use UE4, and the easiest option is to use UE 4.23 because it's the last version that allowed building for web directly from the engine (File -> Package Project -> HTML5).
I had never used UE4 before, I didn't want to overload myself either, but it ended up being manageable, it took me a few days getting up to speed coming from UE 5.5. UE4 has the same logic with less features so knowing UE5 you should be fine too. If you consider going down that road the two main challenges to overcome will be :
- The in-engine tools were less advanced then or didn't exist. For example, I use Modeling Tools in UE5 to make my basic 3D models and to block out levels, in UE4 I had to learn how to do it the old-fashioned way (Geometry/BSP Brushes).
- The toughest one is web compatibility, a lot of things are not supported in web builds with UE4. Playing a video in-game or using post-process is a no-go, lighting has to be baked and is quite limited, shaders are limited too.
There were some upsides though :
- The First or Third Person templates already existed and can be used as a base for your game
- UE4 means you can find more tutorials, forum posts and other resources that have stood the test of time
- Every build ended up working exactly the same from one browser to another, and were much smaller than expected from a UE game (my game The Unknown is 36MB)
So that's about it, you can make a browser game with UE4 but that comes with limitations on graphics. It was my first jam too and honestly, those limitations actually helped me to stay in scope and finish my game, my idea could be done with very basic graphics though. If you consider giving it a shot, the most important advice I can give you is to make a test build after every added feature so you can have answers as early as you can on what's compatible in a browser and what isn't, and figure things out from there.
Good luck, hopefully my answer can be useful to you :)