i keep rubberbanding ONLY in survival mode, and it seems like my console is being spammed with errors? please help

everytime i play on my aternos server (solo or with a friend) i constantly rubberband ONLY in survival though. when i switch to creative i can run around and fly and stuff perfectly fine. i tried looking at my console for help but its just spammed with errors and stuff i dont even understand. im playing with mods but even without this happens just not as bad. i dont have a bad pc, im using ethernet and it only happens when i play on my aternos server. is there anyway to allocate more ram to the server? or any other fix?? please respond ASAP