I had the same issue as well so I just carry him up 1 arm across his chest and the other around his thighs and tilt to aim for the toilet.
Sit on the seat. Definitely standing on the seat isn’t a good idea considering other people sit on it. Otherwise use the men’s room/urinal
I don’t know cause mine sits, but those fold flat stools are fairly small.
My son has been asking to sit in public since he can’t reach most toilets.
I hold my son up while he pees
Sit on the potty