Is there any suspicion or sin in the high monthly salary received by an employee in an oil company, in exchange for few tasks he performs in his specialization in information technology, and is it better to leave this job despite the difficulty of finding an alternative with the same high income?

There is no harm in an employee utilizing their free time to read the Quran or similar activities, as long as they perform their work as required and this does not distract them from their work-related duties. Their salary is permissible as long as they are enabled to fulfill their obligations, and they are not required to leave their job or seek another.