سلام و درود. این کارو میتونید انجام بدید 
def password_validation(password):
if len(password) < 8:
print("Password must be at least 8 characters!")
elif password.isnumeric():
print("Password must contain letter!")
elif password.isalpha():
print("Password must contain number!")
elif password != password.capitalize():
print("Password's first letter should be capitalized!")
else:
print("Your password is correct!")
is_correct = True
return is_correct


while True:
my_pass = input("Enter your password: ")
if password_validation(my_pass):
break