my legs hurt

I started "working out" a few weeks ago. tho it's just walking around for 2 hours. I'm building up the habit and stamina until I can jog comfortably. I was self conscious about running since I can feel my behind moving and I don't want anyone else to see that. but now I can jog for a short amount of time before I get lightheaded so ig it's improvement

my main question is, how do I check if my running/walking stride is correct or safe? I've always have slight pain on my right knees after I'm done walking for long. and when I jog the way my left and my right foot take a step feels different. I think it's something to do with my hips as I lift my legs to take a step, but Idk how to check nor do I know what's correct/not good