Hi Maresh

I have watched all four of them:

Volcano:
To viscous it looks like some underwater scene

Glass shatter:
Doesn't look realistic if you shoot through glass with nothing behind it it doesn't start floating through the air. either there is only a hole, or if it falls it just falls down maybe with a small curve because of the force of the bullit

Carrom: Just didn't get it tbh

Pool:
Strange distracting camera moves which doesn't suit a poolgame and (dynamic)friction is higher so the balls should not keep rotating that long ( especially not along there axes without moving in a particular direction)

If I had to choose I would pick the pool version as a winner because it looked fairly nice.

Just keep working on it it will get better, oh and try studying nature( eruptions) , Pool games, shatter effects so you have a clear grasp on where to get