I've been thinking about this thread today and wanted to suggest something our local church has done to have an open door. They've created a glass porch inside the church, so the big old wooden door is open, and people can see inside, but it keeps the bugs / cats / dogs / heat/cold out.
It's also occurred to me that I would be far more likely to go into a mosque or synagogue that was open for people to just look around than I would a church, because I've never been in a mosque or synagogue and I'd be curious. I've no idea if that's even slightly useful, but it was a surprising realisation! I was raised broadly Christian - Christmas, Easter eggs, pancake day, things like that, and I know the stories around those days because of school. But never actually went to a church for a religious reason. I can see other faiths from a more academic viewpoint, I think, but Christianity feels more of a pressure and an expectation somehow.
I know you've said you want to help your community, and you're limited because your older members are staying home. But I think that's just the point, if you want to help your community there's far more people who aren't part of your church, and don't want to be, than are. If you just want to help people then I think it's important that any thought of preaching or converting is put aside. Our local methodist Church have been putting posts on Facebook for anyone who needs or wants anything to get in touch, from people needing shopping collected or medicines, to just needing to chat to someone on the phone because they're shielding alone. There's no religious subtext, they're just people who want to help other people by doing what those people need, not what they think they should need.
Pre covid the methodist Church rented an industrial unit and had a soft play and cafe there. Non profit, so very cheap. And it was just a soft play and cafe, no religion at all. In fact if you didn't know it was church run you'd have no clue.
But one Christmas I felt comfortable going into the church itself for the first time, because the people outside welcoming people were the people from the soft play, and I didn't feel like they would press religion on me. And they didn't, I bought some Xmas cards, and tea and cake, and DD played with the craft stuff they gave her. It was lovely. But if I had wanted to explore a spiritual relationship with them then I would have felt very comfortable doing so.
I think the upshot is that you can't encourage people into religion, they will come to you if they want to. The important bit is being there if they come, and being the place they think to come to. For that you need to already be in their lives in some way, without pushing them away by actively trying to push faith onto them.