any easy way to solve problems on this theory

Solve more examples.

first see example question solve it then see the answer and see what mistake you have done.

First of all be familiar with the rules given in almost all refreshers then following those rule you give IUPAC name to the compound.

first of all mark the numbers on the carbons of compound after writing the compound on your answer sheet.

mark the carbon number according to the longest chain rule.

then follow lowest locant rule.

then write the IUPAC name of compund with correct suffix according to compound.

BY PRACTICING MANY PROBLEMS YOU WILL GET IT>
THEN YOU WILL SAY THAT IT IS VERY EASY>

hope you get it.

THANK YOU 

It is quite easy to solve these problems.

All that is needed is practice. Solve questions regularly and slowly your organic chemistry will be as strong as anyone else