Hello,
To be honest , getting a visitor visa is very difficult from Morocco.
Your boyfriend would have to show some very strong ties to Morocco that will show that he will return to Morocco after the visit. He would need a good sum of money in his bank account for several months, and the evidence of how he got the money, he would also need a really good paying job that he would be returning to, as well as a house that he owns would really help.
There are those that have all that evidence , and they still get refused because they are considered a risk of not returning to Morocco.
You can give it a try, but the odds are really against him I'm afraid.