Basic Python RPG combat

Hey ya'll I'm brand new to python/programming and have been doing some online courses. I decided to take the day off of taking notes and such and try to challenge myself with some random while loops that simulate different things in dnd. I'm currently stuck on my simulated combat, and I know I'm on the right track but obviously it's not working. Some pointers would be much appreciated.

import random


monster_hp = 25
strength = 5
ac = 17
hp = 25
combat = True
current_hp = monster_hp
dmg = 0
hit = False


def roll_to_hit(hit, ac):
    hit = random.randint(1, 20)
    return hit
    if hit >= ac:
        return True

# print(roll_to_hit(hit))


def roll_4_dmg(dmg, strength):
    dmg = random.randint(1, 10) + strength
    return dmg
    print(f"You hit and did {dmg} damage.")


# print(roll_4_dmg())


def damage(current_hp, monster_hp, dmg):
    current_hp = monster_hp - dmg
    return current_hp


# print(damage())


while combat:
    if current_hp > 0:
        inp = input(r"A monster has appeared what will you do? ").lower()
        if inp == "attack":
            roll_to_hit(hit, ac)
            if True:
                roll_4_dmg(dmg, strength)
                damage(current_hp, monster_hp, dmg)
            else:
                print("You missed!")
                inp = input(
                    r"A monster has appeared what will you do? ").lower()
    else:
        print("You have slain the beast!")
    break

Ok so there are a lot of problems with your code and I will try going through them one-by-one.

In your first function -

def roll_to_hit(hit, ac):
    hit = random.randint(1, 20)
    return hit
    if hit >= ac:
        return True

The moment you return hit the function is going to end and will not check the hit against the AC. And you dont need to pass in hit as an argument. What I think you were looking for was something more like this -

def roll_to_hit(ac):
    hit = random.randint(1, 20)
    if hit >= ac:
        return True
    return False

Your second function as a similar problem where you return a value and then try to execute another command. It also takes in an unnecessary argument dmg. It should look more like this -

def roll_4_dmg(strength):
    dmg = random.randint(1, 10) + strength
    print(f"You hit and did {dmg} damage.")
    return dmg

Your third function is fine apart from the unused argument current_hp it can simply be -

def damage(monster_hp, dmg):
    current_hp = monster_hp - dmg
    return current_hp

Now in your combat loop there are a whole lot of errors mainly due to the fact that you don't seem to be storing/using the values returned from your functions (I highly recommend you read up on how functions are expected to work in python) From my understanding of what you are trying to achieve here is what I think you were going for -

while current_hp > 0:
    inp = input(r"A monster has appeared what will you do? ").lower()
    if(inp == "attack"):
        if(roll_to_hit(ac)):
            damage_done = roll_4_dmg(strength)
            current_hp = damage(current_hp, damage_done)
        else:
            print("You missed!")
print("You have slain the beast!")

Frankly its a pretty good effort for someone new to programming, you need to read up on how stuff stored in variables actually changes (given your extra arguments in the functions I have a feeling there a slight misunderstanding there)

*Also on a different note, your roll_to_hit function is only going to 'hit' 15% of the time as it is right now so it might take a few 'attack' rolls to test out the program