How do I get rid of certain text

[perfringo]

Some observations:

'Explicit is better than implicit': datetime.datetime.today() says explicitly that I am interested in (to)day. datetime.datetime.now() says implicitly that I am interested in current point of time. You will have correct number of days in both ways but it's zen to signal your intentions explicitly.

Your current way of taking input from user can be optimized. You can ask input once and parse date from that without converting input. There is strptime (string-parse-time) method in datetime. You can do this way:

>>> answer = input('Please enter your birthday in dd/mm/yyyy format: ')
Please enter your birthday in dd/mm/yyyy format:  01/01/2000
>>> birthdate = datetime.datetime.strptime(answer, '%d/%m/%Y')
>>> (datetime.datetime.today() - birthdate).days
6801

You will get ValueError if user input is not in correct format.