@XGHOSTMANU I think you put the input in int()

@XGHOSTMANU like this b = int(input("Whats your age?"))

@XGHOSTMANU on line 15 you are adding integers and strings.

@IsaacCannon correct. he/she must either change, on line 3 add int() and then put the input code in the brackets, or on line 15, change d = 300 + b - end - start to d = 300 + int(b) - end - start.