My friend CW had
grand mal seizures (major epileptic 'fits' for which he had a 'brain pacemaker' fitted which was a little successful). Sadly he died after a seizure when he was home alone, about 15 years ago.
He was quite capable, we were assistant cub scout leaders (UK) together and whilst he couldn't be solely in charge of the kids he could lead activities and games. He also took part in climbing, hikes, watersports, etc. The principle cub leader (Akela) was determined to help him take a full part as a leader and in activities; both great people. Outside scouting my friend did fundraising for epilepsy charities, playing with a rock band, and helped kids to come to terms with their epilepsy too.
CW had applied for jobs but couldn't get anyone to keep him on; he spent a lot of time playing video games. In some ways it was easy for him not to work, but he would get frustrated that he felt he wasn't contributing; that he was reliant on his parents.
He couldn't work, as others have said, because he might have a fit basically any moment and leave a puddle of blood and require emergency care. Employers weren't keen to take that responsibility on. To be fair, it was quite scary, he did have some warning that he was likely to have a fit (eg when tired) but not exactly when. He'd be walking along and simply fall face first on the floor -- he had a lot of scars on his face and forehead, but refused wearing a helmet.
He had been hoping to get an assistance dog; they can tell when their owner is going to have a seizure; the owner then can get themselves to a safer place, call someone to check on them, et cetera.
My friend wasn't the sharpest tool in the box, but was not stupid. Jobs that suited would probably be low level administration type jobs. But, he would have managed manual labour if he was paired with someone sensitive to his condition, especially if he had an assistance dog (no heavy machinery though!).
Aside: I don't see why your comment deserves downvotes. Recognising one's ignorance on a topic is the first step towards wisdom.