I suggest you try these, in order, and stop when one of them works for you:
- FaceTime
- Zoom
- Google Duo
- Whereby
- Jitsi
Apple and Zoom are highly incentivized to make their video calling work great, even if it costs them money in global infrastructure. P2P media transfer (like Jitsi does for 1:1 calls) is great when it works, but sucks if the IP routes between the respective ISPs suck.
“Cheap - Fast - Good ... pick two”
We use Dialpad (formerly UberConference) for formal calls where the quality is important, but often Zoom for impromptu / informal ones.