“How long does it take to recover from a brain aneurysm surgery?”

If he is very healthy going into surgery, has no concomitant medical issues, has no pre-op neurological deficits or symptoms, and suffers no surgical complications, no neurological injury, and no post-op sequellae, he will probably be be healed up in less than 6 mos, and maybe even less than 2-3 months if all goes perfectly. Good luck!