Hello :)
If you mean in THNK-P2P
Then there are few things that help in that:
1- Use (Set target tick rate) and reduce the number to something like 15, or just keep reducing it until you are satisfied (the lower the number the less the sync data, and the less the game feel responsive).
2- Avoid syncing every frame.
I already did most of that in the template, but i didn't play with the server tick rate, the default is 20, you can reduce that if you feel the game is lagging.