Healer is a harder role to get into starting out but it gets easier once your gear is decent and your confidence overall is improved.

I will say those that Astrologian is a little harder to level since it has a but more to track.

If you want to try high content and not deal with tracking cards, healing, and mechanics at the same time, try playing WHM. They are similar in terms of healing style but more simple so you can focus a bit more on the mechanics.

Healer naturally comes with the pains of being responsible and anxiety is often the main problem of the role. It's something you get used to over time.