The adjective worth is never followed by an infinitive. Use the pattern worth doing something:
✗ Is it really worth to spend five years of your life studying?
✓ Is it really worth spending five years of your life studying?
✗ The ban on smoking in restaurants is worth to discuss.
✓ The ban on smoking in restaurants is worth discussing.
Note also that the active form of the verb is always used, whether the meaning is active or passive. You can say ‘this is worth thinking about’ or ‘it is worth thinking about this’:
✗ History is a subject well worth being taught.
✓ History is a subject well worth teaching.