can you flat tow a 2wd automatic F150?

Not without installation of a switch to allow the transmission to disconnect from the drive wheels. A 4WD vehicle can be flat-towed in 4WD Neutral, but not a 2WD vehicle.

You can tow a 2 wheel drive a short distance with the transmission in neutral, if you will be goin more than a couple miles, you should disconnect the driveshaft from the rear end so it does not harm the transmission, hope this helps.

In the 1950's and early 60's the Automatic transmissions had dual fluid pumps one front and one rear. Making it possible to push start the car because the drive shaft would drive the rear pump and the bands would lock if the selector was in drive this would cause the torque converter to turn hence turning the engine. The car could be towed in neutral with no problems because the rear pump supplied lubrication to the moving parts. Then the Big 3 cheap skates removed the rear pumps to pocket more profits. That's why you have to disconnect the drive shaft.(no lube to the bearings. If I am towing less than a hundred miles I just put the tranny in neutral and leave the engine idling on the towed vehicle the front pump then provides lubrication to the transmission.