How do I say "I want to..."
I know that "I miss you", or "I want to see you", means 보고 싶어

But how do I say for example "I want to be with you forever?"
When I want to say "I want to meet you." do I just have to add - 고 싶어 to 만나?
So would it say 만나고 싶어?

Question

How do I say "I want to..."
I know that "I miss you", or "I want to see you", means 보고 싶어

But how do I say for example "I want to be with you forever?"
When I want to say "I want to meet you." do I just have to add - 고 싶어 to  만나?
So would it say  만나고 싶어?

Answer

I am not capable of explaining grammatically :/ Sorry but I hope it helped.
However, I assume you will be fine if you just subtract 다 and add a remnant letter to 고 싶어.
For example, 하다 -> 하고 싶어, 먹다 -> 먹고 싶어, 보다 -> 보고 싶어, 만나다-> 만나고 싶어

Answer

I want to be with you forever -> 평생 같이 있고 싶어 or 평생 함께 하고 싶어.
만나고 싶어