Fussy eater

My 14 month old is a fussy eater. He loves trying new foods but after two bites refuses to eat. He also refuses to sit still to eat at the table. His grandmother, in a bid to get him to eat well, bribes him to eat with blueberries or biscuits and let’s him play while following up with a spoon of food to eat. I’m concerned that these are bad eating habits, but don’t know how to change these feeding behaviors! Any tips please? Help!