Q:

Repetitive days of the week code

Could someone help me shorten this code, please?
while cd == "monday":
    if cp == "0":
        for v in mon.values():
            print(v)
            break
        break
    elif cp == "1":
        print(mon[1])
        break
    elif cp == "2":
        print(mon[2])
        break
    elif cp == "3":
        print(mon[3])
        break
    elif cp == "4":
        print(mon[4])
        break
    elif cp == "5":
        print(mon[5])
        break
    cd = False

while cd == "tuesday":
    if cp == "0":
        for v in tues.values():
            print(v)
            break
        break
    elif cp == "1":
        print(tues[1])
        break
    elif cp == "2":
        print(tues[2])
        break
    elif cp == "3":
        print(tues[3])
        break
    elif cp == "4":
        print(tues[4])
        break
    elif cp == "5":
        print(tues[5])
        break
    cd = False

A:

You could simplify your code to look something like this (warning: I didn't test my code, so you should double-check to make sure it functions identically to the original)
days_map = {
    "monday": mon,
    "tuesday": tues
}

day = days_map[cd]
if cp == "0":
    print(day.values()[0])
else:
    print(day[int(cp)])

Several notes:
In your code, you use a while loop, but in every case, immediately break out of it, either by literally using break or by making the conditional false. What you want instead is an "if" statement. However, because the "if" statements are almost identical, you can simplify it completely by replacing it with a call to a dict. 
(In case you aren't familiar with what dicts are, they're really nifty data structures that make life insanely easier. As you can see, they helped turn a large chunk of code into just 10 or so lines! Here's a link to CodeAcademy which gives an introduction to them))
I'm assuming that mon and tues are dicts of some kind -- I made another dict (days_map) to refer to them. This is a common technique in Python -- whenever you have a large amount of if and elif statements, check to see if you can somehow fold things into a dictionary so you can need to make only a single call.
Your for loop is also redundant. If you have a break immediately after, then it's equivalent to simply printing the first value.

A:

Let's proceed step by step :

WTF are these while loops for ?!

If we enter the first while block then by definition cd == "monday". Now either we encounter a break and we exit the loop and cd still has the same value or we execute cd = False and we exit the loop and cd is now False. As a summary : it doesn't matter what happens, we exit after a single iteration - it looks like an if to me. A similar arguments holds for the second while.
if cd == "monday":
    if cp == "0":
        for v in mon.values():
            print(v)
            break
    elif cp == "1":
        print(mon[1])
    elif cp == "2":
        print(mon[2])
    elif cp == "3":
        print(mon[3])
    elif cp == "4":
        print(mon[4])
    elif cp == "5":
        print(mon[5])
    else:
        cd = False
elif cd == "tuesday":
    if cp == "0":
        for v in tues.values():
            print(v)
            break
    elif cp == "1":
        print(tues[1])
    elif cp == "2":
        print(tues[2])
    elif cp == "3":
        print(tues[3])
    elif cp == "4":
        print(tues[4])
    elif cp == "5":
        print(tues[5])
    else:
    cd = False

You may wonder why I used elif instead of if for the second loop. The reason is the fact that if cd == "Monday" at the beginning, the value would either stay the same or become False, thus `cd != "Tuesday".

WTF are the for loops for ?!

As you break in the first iteration, there is no point in using for. I'd need to know much about the object you are using to simplify stuff.

Why so much duplicated code ?!

Avoid any duplicated code. It's hard to write, to read and impossible to maintain.
if cd in ("monday","tuesday"):
    day = mon if cd == "monday" else tues
    if cp == "0":
        for v in day.values():
            print(v)
            break
    elif cp in ("1","2","3","4","5"):
        print(day[int(cp)])
    else:
        cd = False

