Modifying weapon damage

Is there a way where I can modify weapon damage? So fists will kill in less hits to oblige the player to conserve ammo, and alter the gameplay?

Thanks
~ Nafmunacra

In vanilla doom, you can: modify PROJECTILE damage (plasma, bfg, and rockets - but not radius damage! Such as rocket explosions, always do the same damage), modify the number of firing frames the weapon goes through (so you could make the fist hit 3 times instantly), OR modify the monster's health. But that makes all weapons stronger.

If you want to use advanced features, check out decorate.

How would I be able to edit the original Doom files? And could you explain Decorate a bit more please?

No

WhackEd

Decorate

You should not expect to ask such broad questions on the forums. If you have a specific problem people will probably be willing to help. However, if you take a glance at doomworld's own editing pages you'll find what you need.

Also, since you are a beginner you may want to start out simple - make some vanilla maps without modding the game so you can get a handle on mapping first. Then, do some research on your own about modding the game.