Assalaamualaikum,
I am working in a company, my job will not have much effort and some times i will be free from any work. I don’t have any job to do in the office, so i will use that time for my personal works/Islamic literature reading, etc. Please i want to know that is it correct to this, what islam and shariah say about this matter.
Jazakallah,

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

In this work, you are subject to the same ruling of the private employee whose benefit is estimated for a particular period of time. If he is at his employer’s disposal during that period of time and does not abstain from work, he would deserve his complete wage, whether or not he is given assignments.

Subsequently, it is permissible for you to utilize your free time during your working hours in what you have mentioned. For further benefit, see Fatwa 124879.

Allaah Knows best.