From Ohr Avigdor Shaar Bitachon by Rabbi Avigdor Miller
A person should choose a vocation for which he has an inclination.
This theory is found also in the Gemara (Brachos 43b) and in Koheles. The idea is that each man is created with a natural inclination towards one or more specific kinds of vocation. When a person is able to find something that pleases his nature, that is clearly the most fortunate choice.
That is the theory, and we find it confirmed in the Gemara that each person is generally satisfied with the way he earns his living. In fact, some people love their vocation. That doesn’t mean they are madly in love with it, but they have an affection for that kind of work and they don’t want any other kind of work. This is inherent in the way people are created.
Furthermore, in the Gemara we find that when Hashem distributed the land of Eretz Yisrael to the twelve tribes of Yisrael, He gave each tribe a portion of land matching the nature of that tribe. For instance if a tribe lived near the seashore, they loved the sea and were seagoing people. That means they traveled on boats and made a living from the sea as fishermen. So we see from the Gemara that the people of each tribe were given the opportunity to fulfill their destiny in the vocation they were happy with
In most cases people end up doing the kind of work that’s suited to them
If a man is able to discover what that is for him personally, he is best off, because he will be most satisfied with his work. Actually, Hashem controls the world, and therefore in most cases people end up doing the kind of work that’s suited to them. If it should happen that a person doesn’t like what he is doing, it doesn’t mean he shouldn’t work. Maybe in the course of time he’ll discover something that suits him better.