The idea is good
the idea is new and I wonder how the OP came up with such a good business story...
Yes, the idea is new and the cryptocurrency community always likes innovative concepts than projects imitating previous project concepts is the reason why I believe it to be a good idea.
OP said, " I have a desire to start a business". Technically, it's his long-time dream, not a business story he can come up with today or days ago.
Not speaking for the OP but these are the impression I had when I read the OP's post.
OP, if you are really a beginner in all of this and you have to ask here about the legality of the exchanger business, I'm afraid it's not for you.
OP, never said he's a beginner in the cryptocurrency space. However, he's yet to know how things work on this forum and the business advertisement that is allowed.