Hi @soulsistashakti ,
both your STEEM Power and your Steem Dollar earn interest. Currently Steem Dollar receive 10% interest. This is automatic by just holding them in your wallet, no action required from you.

Thank you very much and thank you for your efforts to help the community better understand Steem :)

Your are welcome :) This is a great community.

Is the interest rate on Steem power and Steem dollars the same?

No, it is not the same. Calculating interest on Steem Power is a bit more difficult - it is certainly more than 10% just because Steem is also inflating quite a bit over time. This article offers a calculator for Steem Power interest:

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