FYI- the gate on left is perfectly level and right is close to being level

Yep ^^^^ or a metal turnbuckle. Of course if the post is not solid, it will not matter and will not last.

That’s why I’m wondering if I can brace the post to the house because there is not getting any better with the post since the gas line is under it. the post

Brace it, no, solidly attach it possibly. Tough to tell what is there as it looks open, metal corrugated roofing and lack of something to attach to in the picture you currently show.

"FYI- the gate on left is perfectly level and right is close to being level"

Not for long; gravity doesn't sleep. You're not getting out of a diagonal brace.

You may brace it against the house.

You should add the diagonal brace.

Gate wheels will add to the ease of opening/closing the gate. I recommend the gate wheelswith springs.

Hi, just looking at your picture it looks like your driveway is pitched away from the house. You may have to raise the gate to get the clearance you need.

Good Luck Woodbutcher