Pro tip: if you want realistic Karlson movement, check this out: https://github.com/Legendized/Karlson-Movement-With-Wallrunning. It's a modified version of Dani's Karlson movement tutorial and the wallrun is easily customizable. You should really check it out! And if you want the shooting bit, just follow the tutorial from Dave / Game Development because he has 2 tutorials on projectile shooting. The second one is about the projectiles, so you could use it for explosions and stuff. And also don't use microgames as a starting point. Just make a new project! If you're new to Unity, consider following some tutorials first.
Sorry if I wrote so long. I hope this helps.
GG