In negatives and questions, 'ever' asks if something happened or is true at any time. It means 'at any time' but in a no or question form.
I don’t ever want to go there.
Did he ever call you?
'Ever' adds strong meaning to words like best or fastest. It shows this thing is the most or better than all others at any time.
This is the best movie ever made.
She is the fastest runner ever.
'Ever' shows something may happen at any time in the future or in a situation. It means 'if at any time this happens'.
If you ever need help, call me.
If she ever comes, tell me.
Sometimes, 'ever' means 'always' or 'very' in a special way. It is used to show surprise or strong feeling about how often or how much something is.
Why do you ever say that?
She is ever so kind to us.
'Ever' is part of special expressions to mean 'forever' or 'always'. It shows something continues without end, often in poetry or old language.
Ever and ever, the story was told.
He will love her ever after.