I don't have enough storage to update my laptop

I tried to update my Laptop which is the MacBook Air 13" but it says I do not have enough storage to update it, I have tried to get rid of as much needed data but I still don't have enough. also I cannot find where it says what my storage is being used up by or how much storage I have left. I was wondering if you could help me find where my storage is located and also how much I need to delete to have enough storage to update my laptop