I’ll be driving and the tac will drop all the way then go back up and the speedo does it as well and also the headlights dim when I give it gas and sometimes it feels like it’s hesitating please help

 

Sounds like an electrical issue. Start off checking all of your grounds, and battery connections. Check the battery, and maybe get the alternator tested. Not sure if the 5th gens have an ELD, but that could be a culprit as well.