For your first 3d game, its awesome! It really made me think of how usually in fps games dumping tons of bullets into enemies is the default and not actually making every bullet count. I have few notes though:
- I usually had no idea if my bullet actually hit an enemy unless i stuck around and made sure their death animation played. Adding even a single death or AGH! sfx, as well as blood particles to the enemies when shot dead would've made a real difference
- I know its your first 3d game, but adding a skybox and even a single tileable texture (there's many CC0 ones online) wouldve made the game standout more and look better.
- when the player gets hit, it isn't really obvious besides the knockback and having to monitor the HP count. Adding a hit sfx to the plater as well as red vignette flashing gives better indication
- the jumping personally felt a bit floaty, , but i suppose thats a stylistic choice because of the high platforms, which isn't really fundamentally bad
- adding a muzzle flash to the gun and even procedural recoil wouldve made gun's gamefeel better
Overall great job, and I'm looking forward to your next 3d games!