ABSOLUTELY THIS... you love your baby. You've said so yourself.
I'm going to be brutally honest with you here @solosunflower - you need to STOP RIGHT NOW with this fantasy that baby will have a perfect, happy life once adopted. That is NOT the most likely outcome.
Firstly, as others have said, your tiny newborn will be placed in foster care. Passed along from one person to another at a time when nature dictates he should be bonding with his parent.
Then once adopted - and even if it's a well-off couple and he is given all the worldly goods his heart desires - anything can happen. They could split up. Abuse him emotionally or physically. Plus, he will live with a lifelong sense of rejection. He'll seek answers. He WILL come looking for you one day.
YOU WILL BE INFLICTING TRAUMA ON YOUR BABY - is that what you want??
All your baby needs is you. Staying with his mum, no mattter how imperfect she feels she is, is his best chance of a happy childhood and balanced adulthood. THere is plenty of help and support available for new mums like you - put your pride in your pocket and take it.
Forget about your useless mother and ex-partner. Focus on your baby - that's the strongest, most unconditional bond of love you will ever have. It'll be the making of you.
Right now I get that you're terrified. We all were in the last few weeks of pregnancy, But PLEASE put this rose-tinted view of adoption aside and prepare for the birth of your child on the assumption that you will keep him. Accept help.