If you owe a huge amount of money to a student loan company then yes they could garnish your wages for the student loan debt.
The student loan company would have to take you to court and sue you in court for the student loan debt and then they would have to get the judges and court order to garnish your wages.
I've known a few people who had their wages garnished over student loan debt so you need to try and work with the student loan company on the debt.
Pay as much as possible as you can on the student loan debt because it will also harm your credit score if you don't pay back the student loan debt.
Don't wait until the student loan debt gets too much and then they take you to court over it.
Make payment arrangements and pay off what you can and after around 20 to 25 years you can usually have the student loan debt forgiven.