Yes, there are several platforms that offer free online courses for postgraduate studies. Some of these platforms are:

1. Coursera
2. edX
3. MIT
4. Khan Academy
5. FutureLearn
6. Open Yale Courses

Keep in mind that while these resources can provide valuable knowledge and skills, they may not always offer formal postgraduate qualifications. Additionally, if you're looking for accredited programs or specific qualifications, you might need to explore other options that may involve some costs.