If you had to choose both one zoom and one fixed lens as your go to portrait lens. What would they be?
First, you should tell us what body you use. You could help get a better answer by explaining what gear you have available, and posting some exampoes of what type of portrait you like. A prime lens will do a better job than a zoom, but a zoom has versatility and if you pose your subject far in front of the background, the background will be blurred.
You have received lots of answers, including many that assume you use the same body they use, whatever that is.
The answers from those who explain which body and lens to match they use should help you, it makes a huge difference, and it shows that they understand the difference.