Steve's church is doing live stream using the Blackmagic ATEM Mini Pro. But he's having issues with the church's laptop, which is older keeping the stream going, while also powering a Powerpoint to project on the wall. Each will have different resolutions. Leo says that the projector is analog VGA, while the ATEM is HDMI out. The good news is that the ATEM has multiple HDMI ports. Leo suspects that the old laptop just has analog out. You could get an adapter. Burke in the chatroom recommends the Cloner Alliance Cloner Box Pro. It's a video capture box that will convert the analog into HDMI to plug into the ATEM. But the issue is no audio comes in.
But it's high time to get a new laptop if you have the budget for it. The downside is that you'll also need a USB-C to VGA adapter to go from a new laptop to the projector.