We use 'ever' and 'never' in the present perfect to talk about things you have/haven't done in your lifetime. These two are fairly common.
'Ever' is used in questions - Have you ever been to Paris?
'Never (=not ever) is used in negative statements - I have never eaten sushi.
'Even' is used to add some new or interesting information to an answer. "I have never eaten sushi, I have never even been to Japan.", or with positive forms too. "I have been to Paris, I have even eaten croissants in Paris."
Hope this helps