After ivan iv took power, how did he deal with the code of laws?

When Ivan 4 took over power he sought to revise the laws and make them clear. He speiafically introduced new laws that established order in Russian Government. under him, government operated efficiently which had the effect of introducing efficiency. the gains of his rule are also enumerated in his success in expanding Russia.

Ivan IV revamped and reorganized the code of laws to make government more efficient.

The law code that Ivan IV was replacing dated from 1497;  he instituted his new legal code in 1550.  A main feature was the reorganization of Russia's government into departments, each with a specific function or responsibility.

Ivan IV was also known as "Ivan the Terrible," because he could be quite ruthless in achieving his aims.  He is also known as the first tsar ("caesar" or emperor) of Russia, for consoildating and strengthening his power and expanding Russia's territory.