Solve quadratic equation in standard form The first code I ever wrote, sorry that the prints are in German.
I tried to do some code improvements myself but well whenever I do I fail.
Hopefully somebody can help me improve my coding skills.

while True:
    print(" ")
    print("ax^2+bx+c ausrechen UwU, Bitte Achte!!! Bei Kommazahlen . benutzen, nicht , Beispiel: 0.5 0.7 1.6")
    import time

    print("Auf ein Neues?")

    U1 = input("input a ")
    I1 = input("input b ")
    O1 = input("input c ")
    if (U1.isalpha() or I1.isalpha() or O1.isalpha()) is False:
        print("doing some math")
        a = float(U1)
        b = float(I1)
        c = float(O1)
        if ((b * b) - (4 * a * c)) &gt; 0:
            q = float(((b * b) - (4 * a * c)) ** (1 / 2))
            x = float(2 * a)
            y = float(-1 * b)
            z = float(q * (-1))
            result1 = str((y + q) / x)
            result2 = str((y + z) / x)

            print("Nullstelle1=" " " + result1 + "")
            print("Nullstelle2=" " " + result2 + "")

            abc = float((-1 * b) / (2 * a))
            Moo = float((4 * a * c) - (b ** 2)) / (4 * a)

            cba = str(abc)
            oom = str(Moo)

            print("Scheitelpunkt: (" + cba + "|" + oom + ")")

            if (a &gt; 0) is True:
                print("Nach oben geöffnete Funktion")
                print("Schnittpunkt mit der Y-Achse ist" " " + O1 + " ")

            else:
                print("Nach unten geöffnete Funktion")
                print("Schnittpunkt mit der Y-Achse ist" " " + O1 + " ")

        else:
            print("sorry, geht nicht da eine negative zahl unter der wurzel sein würde")
            time.sleep(3)
    else:
        print("nur Zahlen bitte")
welcome to code review!

The first thing I want to do, is to put the code into a function. This separates it from anything else you might run, and allows you more control. I've used the name quadratic_solver and instead of taking input(), it now takes three arguments which are the coefficients. I've also added a docstring which briefly explains the function's purpose. 

My German's not very good so I've just left your comments in; apologies if they're now incorrect. As per PEP8 (python's style guide), I've put your import before the function at the start of the file.

import time


def quadratic_solver(a, b, c):
    """
    Solves quadratic equations of the form ax**2 + bx + c
    """

    print("ax^2+bx+c ausrechen UwU, Bitte Achte!!! Bei Kommazahlen . benutzen, nicht , Beispiel: 0.5 0.7 1.6")

...



Now, if you want to check the type of your arguments you can do a simple:

type(val) is int or type(val) is str for example. 

To loop over several values we can use a generator. Here, we loop over all values in a list [a, b, c] and ensure they are NOT all ints:

if not all(type(coeff) is int for coeff in [a, b, c]):


I'm not 100% sure why you're checking the type but perhaps your inputs are delicate in some way.

The rest of the code is fairly unchanged. I have however removed a lot of the casting to floats and strings.

If you want to concatenate strings with variables, you can use an fstring. This is of the form:

print(f"Nullstelle1= {result1}")


Where any variables are given in {} and an f at the start of the string denotes to put the variable inside the string as a string.

fstrings can also contain code, so I've used a ternary operator instead of your if else statement:

print(f"Nach {'oben' if a &gt; 0 else 'unten'} geöffnete Funktion")


I've eliminated a few extra variables and brackets too, just for neatness. I'd recommend changing your variable names perhaps to something clearer, and adding a few comments to show what's going on.

Putting this all together, we get:

import time


def quadratic_solver(a, b, c):
    """
    Solves quadratic equations of the form ax**2 + bx + c
    """

    print("ax^2+bx+c ausrechen UwU, Bitte Achte!!! Bei Kommazahlen . benutzen, nicht , Beispiel: 0.5 0.7 1.6")

    if not all(type(val) is int for val in [a, b, c]):
        print("doing some math")

        numer = b * b - 4 * a * c
        if numer &gt; 0:
            q = numer ** (1 / 2)

            result1 = (-b + q) / (2 * a)
            result2 = (-b - q) / (2 * a)

            print(f"Nullstelle1= {result1}")
            print(f"Nullstelle2= {result2}")

            abc = -b / (2 * a)
            moo = (4 * a * c - b ** 2) / (4 * a)

            print(f"Scheitelpunkt: ({abc}|{moo})")

            print(f"Nach {'oben' if a &gt; 0 else 'unten'} geöffnete Funktion")
            print(f"Schnittpunkt mit der Y-Achse ist {c}")

        else:
            print("sorry, geht nicht da eine negative zahl unter der wurzel sein würde")
            time.sleep(3)
    else:
        print("nur Zahlen bitte")



Finally, to call your function, you can now put the following:

if __name__ == '__main__':
    quadratic_solver(1.0, 2.0, 3.0)



Wrapping the function in the if __name__ == '__main__': ensures the function is being run from the right place and not externally. 1.0, 2.0 and 3.0 are just some example coefficients.

I would also consider removing the time.sleep(3); what is it for?

EDIT:

For the type checking, per @AlexV's comment, if you're checking an input is of a valid type, it's better to check it IS that type, rather than ISN'T another type. So the condition would actually become:

if all(type(coeff) is float for coeff in [a, b, c]):


You could even use Python's new type hinting if you like:

def quadratic_solver(a: float, b: float, c: float):
    ...

```