On this page of the guide to Battlefield 2042, you will find information on how to take over sectors on maps.
As in the previous games in the series in the Conquest mode, you will have to take over the sectors scattered on the map. Each such sector will have a number of sub-sectors. To control the whole sector, you have to take over each of the smaller ones from the enemy.
The process is quite simple. Enter the territory of a given sector, and then eliminate all opponents there. The game will inform you about the power balance and how many people from a given team are near the point.
If there is no member of another team in the area, then the taking over will start automatically.