Past — Present — Future is the most universal three-card spread and the best first reading if you are just starting. It suits a situation already in motion, where you need to see the movement: where it came from, where it stands and where it is heading if nothing changes.
It doesn't suit choices between options, and it doesn't suit questions about another person — those need positions reserved for that person. What it is excellent at is the first look: do it, and you will know which spread to take next.

