If by "Piplene" you mean cross country pipes than SMAW.
If by pipe you mean refineries and processing plants than GTAW may be best.
It takes a good long time to learn how to weld pipe, so think of it as a path with many stopping points.
A cert from your school will at very best open the door for you to be tested someplace else. In the pipe world, welders are most often tested on every job or project they start,,, Especially in field work. So get that into your head right now and begin to get comfortable with the notion... Professional test taker is what you will be.
If SMAW Then you need to master open roots. Most people learn to do this with plate first, in all positions. When you can certify with SMAW plate, open root, in all positions, then you can start thinking about what kind of pipe you would like to weld.
Some pipe requires E6010 roots and E7018 Fill
Some require E7018 all the way out
Many cross country pipelines need to run all passes downhill, but that will come later.
In my opinion, with technical schools; It's not as important to grab the certs as it is to leave with repeatable skills. Lot's of students can pass that test after a few tries, and then after a few months of not welding, cannot come close to passing any test.
Try to leave the school with the ability to pass that test every time you take it... Don't bother certifying and moving to the next project unless you really have mastered the technique...
If you can come in cold to a test and prove that you can do something very well, that is going to open the door. The paper will mean nothing unless you can do it again and again.