Start with the insoles then. It should help a bit until you can upgrade.
I agree, I have these ultraminimalist running shoes that i like to wear around sometimes, but if I wear them to work or out on errands my feet will be killing me, a few mm padding can make a huge difference
this might seem woo, but.... a several years ago, I took a multi week beginner Tai chi class with a bunch of elderly people and rather than focusing on a lot of exotic transitions / postures, the instructor had us spending most of our time in the "empty" posture which looks like you are just standing there.
in reality there are a bunch of subtle guidances about joint alignment, weight distribution, and how to read & react to fatigue based on muscle group.
fundamentally, it's just about body mechanics and it changed the way I approached basic, but prolonged activities like standing still (sweeping, doing dishes, etc) and walking.
essentially, in life we tend to learn a lot of cheating postures to relax muscles while standing which put mechanical pressure on joints. the training is to consciously undo those habits and instead build the surrounding muscle groups up by distributing the "work" evenly with balance/alignment.
as a legit older person, I am also a big fan of Aleve/naproxen sodium, elevation of limbs, and hot water on sore parts.
If Tai Chi isn't your thing, Pilates or Alexander technique training is also great. Many/most opera singers and performing arts people use Alexander technique to help prevent injury.
What @kissinger said is great advice. I had a job where I walked about ten miles a day and insoles made a world of difference. They'll help your knees, hips and even your back.
At least in my experience they were extremely painful for the first couple weeks as your body adjust to the new posture and small muscles which aren't used to being used get strengthened.
A light weight "active" knee brace can also help.
It's not entirely unlikely that working out will help, I had pain after standing/walking a lot after the lockdowns because my legs had weakened and gone out of the habit of doing stuff, and working out did eventually help.
I suppose it depends on what’s actually going on with them but I rub Bengay cream on mine.
Besides insoles and such, I will add fidgeting. Not to sound dismissive, but even if you're standing still, move around as much as you can. The occasional squat, rocking up onto tiptoes, shifting weight, knee bends, etc. Don't let yourself get stiff. I work fast food so I'm often standing in one spot for a while and that is how I survive.