Form 16 related query

Does IT department have any info about the balance we are having in our bank account or it assumes it from the form 16 provided to the employee from employer.

Does IT department have any track of the balance in the employees account and if no then one employee can have any amount of balance irrespective of what he/she shows while filling the ITR ?

Can u please help me in understanding how itr filling works for employees ,does employee can have any amount of balance in their accounts since bank statement is not required for filling itr in case of employees.

Thanks in advance
Aman Agarwal