My teacher asked me to write a program as the following and I don't even have a clue how to start. Any tips Write a python program which displays a simple menu as follows: Python ISBN Conversion Menu...

My teacher asked me to write a program as the following and I don't even have a clue how to start. Any tips

Write a python program which displays a simple menu as follows:
Python ISBN Conversion Menu
1. Verify the check digit of an ISBN-10
2. Verify the check digit of an ISBN-13
3. Convert an ISBN-10 to an ISBN-13
4. Convert an ISBN-13 to an ISBN-10
5. Exit