You want a router with support for this. Presumably you currently have a combined WiFi and router? You would put your WiFi into “AP Mode” (doing only WiFi and not being a router) and then install a router between it and the Internet modem(s). If you’re extra tech savvy, you could do this with a firewall, such as pfSense. If you need it to be as friendly as possible, you’d need to find a router with the feature. This one is around $70 on Amazon and seems like it would fit the bill, but I have no actual experience with it. https://www.tp-link.com/us/business-networking/vpn-router/tl-r600vpn/
Here’s an article that may be helpful (this was a Google search result, I am unaware of the credentials of the source, so you may want to do some addition research of your own.)