My Suv over heats then cools down many times and heater blows cold air?

Hello all I ty for reading this and hope someone could help out
Any help is great
Ty in advance
2010 Ford Explorer over heats goes all the way to red line for a few seconds then returns to normal
Heater also been blowing cold air
Turning on heater and or defrost doesn't help
Temp level doing this many times in a row
But when I get out to check
It is not boiling or hissing

I have " bleed the raideator
And it is not losing water no drips any where
I have no idea what to do
I ty all in advance for any help you can give
Ty Vm
I have also Replaced the thermostat

Is there actually enough coolant in it? How did you bleed it?

I found online a place that said to bleed it by taking the cap off letting it bubble I'll continue to fill it up with water while it was at idle speed with the defrost on high I have also flushed the system completely by taking both hoses top and bottom off I'm bleeding in through the engine and through the radiator so there's no clogs