Me and my best mate(whos male) would like him to adopt my kids
There has no contact and is not on birth certificate he's told csa he is not the father how do we go about him adopting them?

The exact process would vary based on your location, and we don't know where that is. What you are describing sounds like a stepparent adoption. In that case, you would need the other parent of the children to relinquish parental rights to clear the way for the adoption. In many locations, you will need to be married as well, for possibly up to a year before a court will consider a stepparent adoption. This is the best information I can provide based on the limited details that you have provided.

For any user with a similar question, please consider posting your question as a new question, and be sure to include details such as your location, and the current custody situation with both parents for the best information.