From this chapter of Flight Simulator 2020 game guide you can learn how perform the so-called cold start procedure. We show you how to carry out the so-called "cold start", which consists in starting the machine and igniting the engines at the ambient temperature.
The Cold Start procedure, that is, running all the elements of the aircraft from a scratch, looks slightly different for each model, so it makes no sense to describe each of them accurately. Microsoft Flight Simulator 2020 offers a great tool in the form of a checklist, which takes us step by step through all the engine and system start-ups required for every plane.
In time, you will surely learn them by heart by regularly flying your favorite machines. Generally, it all comes down to turning on the power supply, opening the fuel flow, turning on the avionics and starting the engine. Some aircraft models require different individual procedures, which is why the checklists are so useful.
However, if you're in a hurry, you can simply press the Left CTRL + E keys to enable the autostart engines feature.
1 - select the Checklist from the toolbar. If you don't care for the full realism, you can usually skip the first two lists. We start with the Engine start, and then it is worth going through the items of the After Engine Start list. There may be something there to set up properly, not just to check.
2 - Perform consecutive actions from the list. Click on the eye icon, which will point the camera in the right place and highlight the proper button or lever (with a blue color) for interaction. After doing this, select the Tick Item to see what has been already done. This way, go through all the items on the list. Some will only require you to read and check the gauge indications.
3 - After all operations have been completed, the aircraft will be ready to begin the flight.