Hi, I discontinued my 12th in 2008 (BLR). Pls advise if I can still appear for the subjects I fell back on or take the course all over again

Aft I discontinued 12th I started working. I am interested in completing my education after 6 years. Pls advise if I can appear for the subjects that I fell back on or should I take up entire course again due to long break? P.S. This question may appear in wrong category as website doesn't allow.