It’s wonderful that God is calling you back to himself. God has provided us with the way back to him that we all need. Jesus Christ said “I am the way and the truth and the life” (John 14:6). None of us worships God as he deserves, and so we all depend on Jesus’ relationship with his Father. We all ought to ‘feel the need to be baptised again’, as you said, because we all need Jesus all the time.
Baptism is an expression of our trust in God. It says, ‘I believe Jesus when he says that he can save me and bring me back home.’ Baptism symbolizes the death of our old life - that it was worthless as far as getting right with God is concerned - and the start of a new life. But crucially, this new life is not our own, we’ve been made alive together with Christ (Ephesians 2:5).
What I mean by this is that the big event that saved us didn’t happen during our lifetime, but when Jesus died for us on the cross, and rose to new life 2000 years ago. That event took care of our old lives, and gave him the new life he can share with us. So for us today, the big issue is deciding whether to trust Jesus when he tells us that the work is done. Here’s Ephesians again (2:8-9): “For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.” That’s the gospel message, that’s what it means to be a Christian.
Baptism is the symbol that we have made that decision and taken that step. It is a public declaration of your new faith. You don’t need to be baptised (again) to be a Christian, rather concentrate on trusting in Jesus.
Now thats not to say Baptism is an unimportant thing. Being a Christian is about being a part of God’s family (the church) and declaring to that family that you have made that decision. In that sense, Baptism may be a good thing for you to do because it declares to the family that you are a part and helps you publically associate with them.
On this point, while going to church is not compulsory, it is incredibly important and highly recommended. Gathering with other Christians will help you in your own Christian walk, it will help you face tempttions and stay firm in your resolve. So can I recommend that you and your oyfriend try to find a good church that you are comfortable with. By “good” I mean one which publically reads and teaches the bible, which seeks to live as the bible tells them to live, and which is friendy and welcoming. They’re not always easy to find but well worht looking for,
You’re also on the right track with reading your Bible. God wants to relate to you, as an adult, personally. So talking to him (prayer) and listening to him (Bible reading) will really help you. Remember, we all need Jesus all the time. A good church will also help you with this - they’ll encourage you in prayer and Bible reading, they’ll keep reminding you that the gospel sets you free from trying to please God with your own efforts. Find a church that does that, where the people all know Jesus and want to know him better. That makes them just like you, whatever other minor differences there might be.