Recommended basic Shoulder-friendly Rucksacks/Backpacks?

Title. I work from home and spend a lot of time on my walking pad. I have a weighted vest but it destroys my shoulders which means I can't wear it for long and it also hurts my lifting since my shoulders are always fatigued.

Any recommendations for basic rucksacks that can take the load off my shoulders?

I only plan on using it with my walking pad. Due to work, I'm unable to go out much atm.