In the context you gave, he wants Pragya. And he wants Pragya to tell him she loves him too. He wants his old life with Pragya back.
I don't think he wants the baby. This baby is a total superimposition on him. Everyone is saying it's his and he should do the right thing and he is. Becoming a dad is a biological and emotional connection to the baby and baby's mom. He's not feeling that because it's not his baby and he doesn't love Tanu. He's pushing himself to do all this. His body and mind are telling him he's not the dad and he's killing that and believing others! t must feel like hell from his pov. I can totally understand his inconsistencies with the baby.
He has been indecisive in the past and has actually changed for the wrong person, thanks to the team. Instead of everyone watching him make wrong choices if someone he respects told him baby is not his, then we don't have to see him look so lost.
But overall, in the story, Abhi is the prize that everyone wants. He mostly wanted nothing until Pragya came into his life. So his only self interest is Pragya.