Recreational Vehicle Lpg Tank Valve/gauge problems of the 2019 Hyundai Tucson

My 2019 Tucson has been getting horrible gas mileage and also making some strange noises that I'm unsure of what they are. It's also acting like it has no power installing on a pretty regular basis since the dealership has stated nothing's wrong with it and my vehicle health report continues to state nothing is wrong I decided to get a obd2 adapter to place on it so I could see what was happening. While the vehicle is running at idle doesn't matter if it is cold or warm the throttle body sensor does not go under a 10 so it's obviously sticking I don't know if it is defective or if it's been like that for some time but if the throttle body is stuck then that's going to cause it to stall that's going to make it burn more gas that's going to make it run pretty crappy and be kind of hit and miss. The vehicle's brakes are always grinding and squealing. There is also a wine and a tapping clicking sound coming from under the hood I don't know if it's a bad pulley or bearing or a loose heat shield or whatever but it's not injectors there's something under it. The rpms are continuously getting stuck the gauges are getting stuck, this car malfunctions every day.