How old is he? Is he currently partially clipped?
Do try to think of a way to stop him from getting to those places if you can, especially if the fix is simple, such as cardboard and tape.
As it sounds that he is not used to flying, clipping when he is too young can impair flying in future as a young bird needs to learn HOW to fly. Also, clipping only gives humans a false sense of security and gives the bird a huge blow to its own sense of security. The bird can become more nervous and distrustful of humans. It can also be shocked when trying to fly but unable to. Birds are smart and remember many things for a long time. The trauma of not being able to escape a predator or a frightening event will be kept in his mind.
My fischer lovebird came to me already clipped. The breeder said he had just clipped her freshly. The shock on her face when she tried to fly and dropped like a rock off the table edge was heartbreaking and since then she's very aggressive and fearful.
You have to consider the bird's point of view and their emotional and mental health.
Also, some birds just need more time to figure out where the door is. They may prefer to land on the cage bars then climb in. Don't rush him. He needs to familiarise himself first with the cage and the room, both from inside the cage, and also from outside the cage, just like us humans when we realize that buildings can look different from a different perspective. The bird does not know what you know of the room, including spatially and possible threats. Start with closing windows and doors and turning off any ceiling fan, and then leaving the doors of his cage open. Its okay if he doesnt want to come out, but let him process where the "hole" between the cage bars is. Later when he's able to step up and be carried outside, allow him to perch on top of the cage. Leave him there if he gets nervous. Give him time to be more confident of having no dangers in the room. Do these when you have at least an hour or a few hours to spare and buffer in extra time to slowly and calmly get him back into the cage. Don't panic and chase immediately if he flies off to somewhere that is still a safe spot. Let him calm down for a few minutes then try to get him on the perch or finger that you are using for step-up.
The most important thing is to ensure that any "out of cage" time is not stressful for him. Taking him out for 10 or 20 minutes and then rushing him back into the cage is only hampering the bonding process as it reinforces and proves to him, both in his own fear and the stress that birds pick up from human movement and voices, that the outside of cage environment is dangerous.