“Do an additional course to find a better job“. Is this good advice for freshers?
Depends on where you are in life when you are a fresher who just graduated.
Are you from a family that needs you to begin getting an income right after graduating college? Or are you from a family that can run even without you bringing home the bread for a few years or more? Additionally, can your family also afford to spend more on your education at the moment?
The best advice for freshers that will help both these kinds of people would be to get an internship with a proper stipend. Rather than joining some random job that has nothing to do with your education, you might as well suffer a little, and work towards a better future.

Why an internship over an additional course?
Regardless of how many courses you do, you will get stuck at a point in job searches, where the word “experience” comes into play. Choosing to intern and get on-hand experience while you learn about the ropes at your job will ensure that your actual fresher job comes with better benefits. Also, you might get a permanent job at the place you intern! A survey conducted by NACE in April 2012 disclosed that the conversion rate for the interns into full-time employment rate was around 58%.
Internships also give you a huge opportunity to build a connection with professional people which is helpful for you in your career in the future or for learning purposes and knowledge as well.
Another thing to keep in mind when taking advice as a fresher is that the toughest part for a fresher is to get interview calls. A resume with hands-on experience is much more desirable to employers than a fresh resume without having industrial experience. An internship is the best way to enhance your skills and add experience to your CV.
Why an additional course over an internship?
If you can pursue higher studies and can put off being in the real world for a few more years, go ahead. Education is always helpful, and we learn until the day we die, so we are not going to advise you to stop studying unless your life needs you to do so.