I am not clear on whether you want him to be able to get through the gate or trying to prevent him from getting through it. We have Standard poodles and have needed to limit their access up or down tge stairs periodically but they were able to jump over low regular gates, so we found taller gates that swing open by depressing buttons to release the moving section and eorks well for human operation with a couple of problems: they are held in place by pressure points on either side of the wall or stair knoel so the gate ends must line up with some side support. To do that means you are taking a rather precarious step at whatever level it is placed due to the gate using some of the stair step width. I would prefer one that didn’t have a solid bar across the bottom for that reason but without it the dogs can push it over, which might not be a problem for you.
Chewy.com is a pet supply house that carries many variety of gates that might work for you. They are reasonably priced and ship reliably quick. Maybe call them to discuss your needs after shopping online.