Hey there!

A propulsion engineer would only get hired in space centers and other space research groups. So, that makes the job opportunities low because there's not a lot of demand. Ofcourse you could get a job which is somewhat related to your field but if you want a job as a propulsion engineer somewhere the places are not that much in number. If you get your degree from a great college ofcourse that would make things easier for you. You'll have to stand out to get a job like that in places like ISRO because there aren't a lot of spots.