As you play through the story campaign in Destiny 2 Beyond Light, Variks will ask you two disable Praksis’s Conflux for one of the missions. This can be a little bit of a grind, and the game does a poor job of explaining what is actually happening.
The entire process is actually quite simple. When you arrive at the Conflux you need to interact with it to start it up. This will cause three large Vex diamonds to appear in the sky, surrounded by shields.
Waves of enemies will attack you, and you need to fight them off. What is not apparent is that this is pretty much a timed event, tied to the waves. It’s only when you kill a certain amount of Vex that the barrier around the Vex diamond will drop.
When it does, you can then shoot the Vex diamond, destroying it. After that, a new wave will begin, the beam of light between the conflux and the Vex diamond will switch to a new target, and you will need to go through it all again. You’ll need to do all three to finish this mission.
At the end, Praksis will spawn in a massive Servitor to try and kill you, and you will need to take that out as well. This guy is tough, at around Power 1120, so don’t be afraid to farm up for this mission, or tag in some friends to help you out if you need to.