Hey OP, it's not for everyone but market research companies are often hiring folk to do interviewing work - would be dialling on the phones and getting people to participate in surveys over the phone with you (no selling involved). Most companies require a minimum number of shifts or hours per week, but often it's flexible and you can do it around another job/ other commitments. A lot of places let staff wfh now, post covid.
If it's of interest, check out job websites like Indeed and search for "work from home telephone interviewing". Pay varies slightly from place to place, usually 0 hours contract (could be a good or bad thing depending on perspective!) and you might expect to get holiday pay added as percentage on each pay run meaning you'll take home around £11/ £12 an hour (ish... Depends on the company and some places might have different rates depending on experience, might be a tad less, also depends on the projects).
Flyering? Not sure what the pay is like for that - might be pretty knackering though if it's door to door flyering rather than handing out leaflets on the street, but imagine this might be flexible too, around other commitments. Might find adverts for that on Gumtree amongst others, depending on where you live.
Are you an animal lover with experience of cats/ dogs? Local cat sitting/ dog walking companies might be hiring, again I'd have thought this might be flexible also.
Are there office buildings near where you live? If so perhaps there's a company you can register with to clean offices in the evening (or maybe early mornings).
Maybe you could offer an ironing service for residents, locally, or work for someone who has a business like this already set up that needs the help if they're very busy. Might be the sort of job you'd need a car for. Again, this sounds flexible.
Good luck x