You can try the bleed screw at the engine, you can leave front elevated after some heat cycles then check level or you can get the kit from Amazon.
JIFETOR Cooling System Vacuum Purge Radiator Coolant Refill Tool Kit, Automotive Water Tank Pneumatic Vacuum Antifreeze Change Filler Set, with 4 Sizes Adapter Case Hose for Car Van SUV Truck
Amazon.com
Personally I think it’s the temp sending unit from what you describe. Your fan ever come on? Can you make it run where you say you only get to 200? Have you added a heater or changed any hoses? Been into the cooling system at all???? Try unplugging the temp sensor and see if the fan comes on…..🤷🏿♂️