Yes - I know how. Worked with Mosfets way over than dozens of times
I use an underside heater. Stand offs - because the board can't touch the heat source.
Also have a 2 in 1 Soldering Rework station. Use the hot air nozzle side and a slim nozzle. Set the temperature around 250 C. And that's Hot Air Nozzle - not Heatgun. This nozzle has a very adjustable dial in temperature range.
A basic solder iron will not remove a Mosfet. As you have kind of found out
Flux and rosin core 60/40 solder also help. And a set of tweezers.
Do you know how to accurately test Mosfets ? That's very important. And they need to be off board.
Plus have you matched yours correctly? For style, package, voltage and amps