I echo what othersa have already said.
Once the kids get to the age of yours, I expect politness at the table. I never force my kids to eat something they dislike, and they are not to make faces, noises, complaints if there is something on the table they don’t want. If they fuss or act wild, they have to leave “until they are ready to come back and behave nicely.” And this can’t be a threat – they really do have to leave if they can’t be polite.
I tell them ahead of time that when they complain and goof off at the table, it’s very rude to me. I make nice food for them with love and with my time, and they need to accept it in the same kindness with which it is served. Also, at dinner especially, when DH is present after being gone from the family all day, it’s an easy gift the kids can give to him by behaving and helping make dinner fun for everyone.
While you are preparing lunch, perhaps the kids can have some free time to get the wiggles out. When lunch is ready, have them wash up, pause before the table for deep breaths to calm down, tell them “now we’re eating our meal together and everyone will cooperate.”
Perhaps to break the habit, you could do something for yourself to remind yourself that keeping a peaceful table is worth the effort – new candles as a centerpiece, nice music to play while preparing the food? Something simple that brings you joy and helps set the tone you want to achieve.