Ag training is sparse; there's not a lot of it. Upon holding a new commercial certificate, one could go to an ag school, but finding someone to insure you and hire you is another matter.

Before spending the money to get pilot certification and go to an ag school, take the time to research the market; the employment market, and what's involved in ag work. If you're not able to travel now, then ag work definitely isn't for you.

Ag work is seasonal, and it involves moving on a regular basis to where ever you're working, sometimes traveling with the aircraft to multiple locations to follow crops or assignments.

Have you looked into the safety aspects and the hazards and risks?