Helping someone to recovery

Hi I just recently posted, but I feel this is really the only place I have to ask questions.

I caught my boyfriend using and he is telling me he will do anything for me to stay. Each day he’s doing less and less-and the plan is in two weeks basically lock him in my room and get him clean. If that doesn’t work, we both agreed to get him to rehab and professional help.

What do people recommend to help him get clean on his first attempt? He doesn’t have health insurance so getting him medicine might be hard. But I was thinking Gatorade, Advil, and Benadryl to let him sleep? To those that are clean, how can I be motivational to get him through this?

Second, does the craving for this ever go away? Or is it something we -or him - will always be battling? If so, how do you overcome this each day?

Lastly, he’s been saying he wanted to get off for a while. He was embarrassed and humiliated and was going to try to do it without letting me know. For a while he’s been doing just enough to get by...to not feel the flu like symptoms of withdrawing. But sometimes I feel like this whole relationship, what if he was high, what if I don’t know him and what if he doesn’t love him as much off of it? I don’t know much about heroin, or even drugs in general. Sorry if these questions are annoying and if it’s a lot.