state difference between in and at
'At' is used to show the exact position of the first noun in relation to the second. For e.g The train arrived at the station.
-ATdescribes position at a specific point.It's very cold at the bottom of the ocean.-ATis also used with a larger place (a store, bank, airport etc)Let's meet at the bank-ATis used before the names of group activitiesat a party, at a meeting, at a play, at a paradeIN
-INrefers to position within large areas or in spaces that surround something on all sidesMy keys are in my bag. He is not in his office. The car is in the garageON(I added this one too!)
-ONis used as "attached to" or wearingWhich finger do you wear your ring on?-ONalso refers to the surface of somethingMy computer is on my desk. The book is on the shelf