Using NAV after departing w/ATC

What steps should I take before engaging Auto Nav after ATC departure has redirected my flight path miles from my filed route? As of now after my hand off from departure, if I were to steer back to the direction of my filed flight plan and align manually with the route, then engage Auto Nav, my plane wants now return to the first way point entered. So I delete my flight plan and redo. I feel I missing something. Please advise

In the fpl section you can click on the act.leg option to change the waypoint that you’re flying to so it won’t direct you to the first one you entered if u missed it.