Zoom et al have been a frustration and a disappointment to many musicians trying to come together and make music in the Cloud. Latency—the lag introduced by distance and technology—makes keeping a common groove difficult to impossible in a videoconference context.
Real-time session play, rehearsal, or even performance is possible however over several hundred miles with a decent internet connection using audio only software. There are a number of solutions that I have experimented with, but the simplest by far that I have found is Jamulus.
Jamulus is client-server software. You install the client on your home computer and it talks to a server that combines and syncs your audio with other folks' clients and sends the result back to you in real time. The server can be run on your home computer as well, but it's more usually placed on another computer elsewhere. Depending on the quality of internet service and the level of traffic on the regional internet, the server can be quite far away.
Jamulus itself is based in part on the pioneering work in low-latency digital audio transmission by Saebo and Svenson (LDAS) of Norwegian University of Science & Technology, Cacere and Chafe of Stanford University (JackTrip), Alexandre Carot (SoundJack) among many others. While these solutions have been quite successful in optimal but largely academic settings with cutting edge connectivity and equipment, their implementation is largely beyond the reach of the average user. Their user communities are scattered and tend to be jargon-bound, and the documentation is generally patchy and assumes a high level of expertise in its audience.
While Jamulus does represent some technological compromises–for example the audio stream is compressed (think MP3) as opposed to pure signal–the goal was to provide a usable tool with a straightforward GUI interface for transmitting usable if not perfect audio to players. There is little or no need for command line familiarity, and the installation packages for the target operating systems are well built and quite well-documented, as is the GUI itself once the program is up and running on your machine.
Pandemic isolation has acted like a steroid injection on various low-latency projects that have been around for years. The whole low-latency collaboration scene is like a horse race just after the starting bell. All the contenders are evolving rapidly, and may leapfrog each other in terms of efficacy and user-friendliness as their development communities expand and evolve. Jamulus is just, in my opinion, the best option available at the moment for ease of entry and the user community is open and helpful in the extreme. But if you find the technology bar too high for you, don't despair. Keep checking back both in the Jamulus community (particularly Jamulus World Jam Facebook group), and with some of the others I've named above. As all of these platforms mature, their user interfaces and configuration automation is bound to improve in leaps and bounds. Just stay in tune and be ready to jump in when you see an opening in their evolution or in your understanding.