Build stronger support networks through your community and do the small things that are achievable with them. Help slightly larger groups and pressure them to do good things with their bigger numbers.
You're not going to accomplish any politically relevant actions on your own, but you can organize a group of people around a shared hobby, like a knitting circle, D&D group, boardgame group, or whatever. Your little hobby group can all chip in to feed people at a homeless camp once a month - that hobby group now has the skills to help a local union make it through a strike. The local union that owes your hobby group a favor can be pressured into campaigning against a local DA who's causing problems for the homeless community. That union is now a relevant force in local politics. You probably don't have any ability to sway that any more, but the local union with political clout can chip in to larger causes.
People need to stop living in this fantasy world where a great leader unites everyone behind the right cause and we start fixing things. Nobody has ever done that shit. You can't convince a billion people to do something one at a time, and even if you did, they wouldn't know what to do with themselves. Change requires existing networks of organized people who know how to do something other than sit on their thumbs, who can be convinced an entire group at a time. Nothing can be done while everyone is sitting around atomized, but that is a problem that's actually within your grasp to fix.