Just to clarify... I don't do all these things, but, if you are lookig to meet people, think about what takes your fance :
Sport - join a team - join a running group or a fitness class or something like a Couch to 5K or Park runs
Music - do you play anything ? There are so many levels you can contribute something, from joining bands / groups / orchestras / accompanying others / going to groups to entertain others. Or singing, again, can be done at so many levels
Volunteering - if you have the energy to volunteer with something like Scouts of Guides you will join a massive family of volunteers, and make many friends. If you have less time and less energy or just don't like kids you can do something like My local Hospice has local groups who meet in each others houses to plan the odd fund raising event - running a quiz or a dance or something. The commitment is as much as you can offer, but lovely way to get to know a few other people without it being to 'full on'. Or you could volunteer in helping to maintain a building or a campsite. Or cooking at a lunch club.
Purely for yourself (but again to meet others) - a book group.... a craft group... something like 'Knit and Natter..... go to your local Church and ask if they are doing any projects that need volunteers (so our Church needs further volunteers at Toddler Group, in our maintenance Group, in a language cafe, in our dementia support group, running our lunch club, in a creative writing group for EAL folk, or in a feeding the homeless group). Or part of the home befriending Team.
Or you could dance. Or pay ping pong. Or find a darts team.
It's really difficult without knowing what might interest you and what horrifies you 