Can I introduced unneutered male and spayed female cat?

I brought home a feral male cat about four days ago. He’s not aggressive, just scared of people. He’s been checked out and confirmed to not have any illnesses, and is about 4-5 months old. Unfortunately, he won’t be able to be neutered immediately. As of right now, I’m keeping him in a separate room.

My female cat is almost 3 years old and spayed. She meowed at the door of the room the male cat was staying in (not because she knew he was in there, she simply wanted to go in the room because the door was closed) and he would respond back to her meows.

Is it okay to begin the introduction process to get them to meet face-to-face or should I wait until I’m able to get him fixed?