I don't think it would be difficult. My 6 yr old neice came by at Christmas and she kept openening it. You just slide the button and pick the gate up about and inch and it swings open. I dropped a small tack in my button so it would stay open too, that way I just pick it up to open it. It is a heavy duty gate though, so you have to put a little muscle into the picking up part -
I'm not sure. It has a small thumb switch you have to push while at the same time lifting and and swinging it open. Maybe average difficulty for a kid 5-7 but I'd think its doable/learnable. In a way it may depend on the install...I think you can make it so tight that the bottom rails rub each other and that makes it tougher to open and close. Ours is well adjusted so it swings freely.