Paying off debt collection in full, will it increase my score?

Hello all, this is my first time posting in this subreddit so if something is wrong I apologize.

I am trying to rebuild my credit and the way I’m going to start doing that is paying off some debt collections I have.

I just recently spoke to one agency and he said that if I pay $940 he will mark off my original $1200 debt as paid in full to the credit bureau. My question is will this actually increase my credit score or should I be going around this in a different way to increase my score?