I'm wanting to adopt my girlfriends son. He's only three months old and we've only been together 10 months. Would this still be possible? His bio - father is not involved at all, so much so he isn't on the birth certificate either. Any help and info is massively appreciated

You would have to be married at least a year before the court would grant you adoption.

In most places in the US ( Most not all) you will have to be married, and together for over a year, in others you may not have to be married but they will want a "long term relationship" which will be a year at least.

Next in most places the father still has rights, he will have to be notified and get his permssion for the adoption ( he signs his rights away to allow adoption)
Normally the bio father will be more willing to sign away rights, if the mother has been very active in making him pay his child support, since then he can stop paying, if he is not paying support he often does not have much reason to be helpful

In most places in the US ( Most not all) you will have to be married, and together for over a year, in others you may not have to be married but they will want a "long term relationship" which will be a year at least.

Next in most places the father still has rights, he will have to be notified and get his permssion for the adoption ( he signs his rights away to allow adoption)
Normally the bio father will be more willing to sign away rights, if the mother has been very active in making him pay his child support, since then he can stop paying, if he is not paying support he often does not have much reason to be helpful

I live in the UK not US dot k ow if that makes any difference