this might not be what you want to hear but anyway
If you discussed it, researched it, been to info evenings and he is still saying he wants birth children, then he sounds more than reluctant and I think you need to listen to him.
At 30 you are still young in adoption terms, if you can have birth children have them and return to the idea of adoption in 10 years.
If you push your partner into this I think you run several risks
You adopt, you run into difficulties, he says I didn't want this anyway and he leaves ( yexit does happen)
If you start the process nowm it could be two years before you have a child home, then you need a few years for them to settle, then you run into difficulties, you get to a stable place but you are now in your late 30s and your fertility has dropped off and you have problems conceiving.
You adopt and you have so many challenges birth children are just impossible.
Think very carefully about your motivation to adopt, does it overide the motivation to have birth children?
He does sound a lot more than reluctant though, and if he goes along with it for you I think you are on tricky ground.