First of all congrats on releasing your first game. It's a great feeling and you should be proud. This has really solid bones for an incremental idle game. I like that you can see the action happening on the left, and the structure becomes clear once you get past the initial hurdles. For some reason the vibe reminds me of One Punch Man and I can't quite put my finger on why haha.
I also enjoy the amount of things you can progress in or unlock. It's impressive how much functionality there is here for a first release. The music is also a very chill track and fits the laid back gameplay well. I found myself leaving the game on in the background for a while to see how powerful I could become, which is probably exactly what your intention was.
On the presentation side the game currently lacks a bit of clarity for me. When I first open it, it feels closer to a spreadsheet than a game UI and can be a little harsh on the eyes. I would recommend using a more consistent colour palette. If you are making a 2D or pixel art game, palettes from Lospec (Palette List) usually work really well. I get what you were going for with the background, but the lack of colour cohesion makes it feel more like a prototype than a finished minimalist style.
I would also do a quick spelling pass, as frequent misspellings can take away from the experience. Some simple sound effects for level ups, enemies slain, and money gained would also add a lot.
Overall this is a solid entry and a very good first upload. Well done :)