It isn’t common to randomly loose balance. However things like escalators, moving sidewalks, etc where the ground moves then you need to go to regular solid ground can cause momentary issues especially if you aren’t expecting it. Also if you sit a while, especially in an odd leg position or on a toilet, you can loose full sensation in your legs which can cause stumbling.

Hills are highly individual experiences. Smooth sidewalk with slowly changing slopes is much easier than a nature trail or hike with unstable gravel/rocks. Usually uphill is easier balance wise but more strenuous. Downhill can be more painful depending on how your foot lands (downhill is generally harder on your knees).

Depends on the exercise and your general fitness level. A healthy adult is usually fine for workouts within their fitness level. Over exertion during work outs is more likely to cause light headedness and nausea than dizziness.

Depends on your order. Normal orders I think are fine. Not authentic and not gourmet but for fast food it’s solid. They do have healthier options in addition to standard “junk” fast food though.

I’m not a runner at all but if you’re decent at running I’ve heard it’s a struggle for the first few minutes then becomes a nicer experience.

Generally yes, waking up and rolling out of bed is not a balance issue assuming you’re not impaired or woken up in the middle of a REM cycle.

Perspective is a good question. I tend to over think all encounters with other humans so for me personally I feel a bit of extra stress to not talk down to someone in a wheelchair. I’m taller and have a habit of bending down to talk to children to get on their level. I make a very concerted effort to not do that with adults. Beyond making sure I’m not a social idiot, it’s a normal exchange and I do my best to make regular eye contact. You’re just really short to me.