what is debenture redemption reserve and i cant find any study material for that

Faiz, follow the below link. After this, there are four topics- explaining the different methods of redemption of debentures. Also refer to them by clicking on the right panel of topic list.

https://www.meritnation.com/cbse/class12-commerce/studymaterial/accountancy/company-accounts-and-analysis-of-financial-statements/issue-and-redemption-of-debentures/436_2434_5896#slide9_redemption-of-debentures