In addition to all of the suggestions above (know who is in the break and who is chasing, conserve energy, you don’t need to pull, etc.) I would add one further point.
You need to understand how the break formed. Was it a selection off the front or off the back? By this I mean, did you or someone else attack to create this gap or did the rest of the group simply fail to hold the pace?
In gravel races and other events with challenging routes (hilly, crosswinds, whatever) the selection often comes from people just dropping off the back instead of a normal breakaway which is established via an attack. If this is the case you should consider everyone not in the group as dropped - even if they catch back on later they are likely not a threat in the race and you should only be watching the riders who made the selection.
In these cases it doesn’t matter if you don’t pull and it disrupts the effort of your group - who cares? Anyone who catches back on already popped at some point and you should be conserving energy.
If the breakaway was formed via an attack or more traditional means then you have to weigh the conditions above about how much to work to keep the group moving fast and avoid getting caught vs. conserving your energy (basically, see all of the advice above)