How do you check multiple user inputs in a single it sentence?

I'm asking a user a question as part of my code, it is a simple yes or no answer but I wanted to make it so it is not specific wether it has capItal letters or not. I thought the easiest way to do this would to use an if sentence for example: if answer1 == "Yes", "yes": #and then what I wanted it to carry on to do

But I can't get it to work. Thanks in advance!