I usually plan the concept of the song in my head like roughly would it be a Chill Song/Heavy Bass/Party/Mood Swing and then accordingly decide the key.To sum it up,I think what vibes people should get while listening to the song and accordingly plan the key.

yea ! start with the feels first, the chord progression comes later. pretty sure there's a talk about this somewhere in another forum (if i couldn't get anymore detailed). just google it. or use https://www.hooktheory.com/theorytab