sir,how to do conversions in organic chemistry ?

You should practice organic conversions while learning. Learn name reaction first and try to practice their mechanism. Mechanism is the only thing which will clear your basic and make other conversion easier for you. Practice reactions and their mechanism as much as you can, this will definitely increase you knowledge and confidence.

 

For doing organic conversions, you must have strong hold over the reactions of various functional groups. As soon as you read any question of organic conversion, just write the given compound on the left hand side and the required compound on the right hand side. Carefully note the functional groups and the number of carbon atoms in both these compounds.

Then, proceed with the reactions you have learnt for the functional group present in the given compound as to arrive at the desired compound.

You can also refer to conversion tables and charts.