I loved the feel of this game - the movement and weapons felt well done, and it pretty fun to control! Unfortunately, I think the FPS and parkour mechanics fight each other a little, especially with the pistols. If you try and move around the map, you'll just get shot at, and trying to snipe the enemies with a pistol with all that bullet drop off isn't helping make the parkour more fun. That's not to say it's impossible to combine the two mechanics, although more reason to use the parkour would definitely help with that, especially the wallrunning - I was real disappointed when I realised there weren't really any good place to be wallrunning.
With that being said, it's still a really fun game! Gun games were always my favourite game modes in FPS games, and this game puts an interesting twist on that - the better you play, the worse your gun gets. The tracers on the bullets also really helped make the game more enjoyable, which was a great quality of life feature, and I'm so glad that you didn't have a limited number of lives too, since I wouldn't have got very far with them. The graphics were great too - they were simple, but consistent, and the aesthetic ended up working very well. The reloading animation was great too, made me laugh the first time I saw it.
Overall, it was a great concept, and while it could've been implemented a bit better, I still really like the game, and had great fun! Nice work!