Jitsi Meet, but be aware that unless you are running it on a desktop in a chromium based browser, or its desktop app then it will not have end-to-end encryption as an option.
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+1 for Jitsi. Works well, user-friendly, lots of features without looking complicated, not too resource-hungry, lots of ways to extend it. All the other person needs it to click a link, enter a name and allow microphone/camera usage one time. There's also an app for Android and iOS, though you can just as well use a mobile browser.
element call
Jitsi Meet?
vdo.ninja?
I have a small self-hosted Nextcloud with Nextcloud Chat and it can do video though it isn't great. Jitsi Meet is much better but I haven't tried to host it myself. I'm sure there are other options too, though idk what to suggest. Maybe see what's around on Scriptaculous these days?