Benefits of collecting colostrum? Can it help my supply later on?

This is my 2nd baby and I really wanna give breast feeding another shot, with my first I had so much trouble producing and I keep seeing people collecting colostrum and would like some more information about it! Here are my questions

1.what are the benefits ?

2.When did you start collecting ?

3.Did it help your milk supply come in faster?

4. If I start collecting and can’t produce can I mix with formula to get some of the benefits ?

5. What other reasons is it used for?