What food to teach baby (10month old ) to chew food ?

You can try downloading the app solid starts. They show how to cut food according to age to prevent choking due to food size. Baby may gag when they first try out. That's normal. It may take some time for them to figure out how to chew. Importantly never leave them alone while eating, always be there to monitor.

soft vegetable sticks like steamed carrot, or soft avocado

by demonstration!