Dear Sudipta,
Would have been better had you mentioned the type of the establishment such as a factory or shop or other type of establishment for the reason that as of now the process of payment of wages including deductions on certain specific heads has been covered by the special enactment viz., the Payment of Wages Act,1936 the applicability of which is restricted vide sub sections (4)(5) and(6) of its section 1. Moreover, the limit on the amount of loans and advances is subject to the provisions of the establishment-specific law applicable to the employee.
Yet, the subject-matters of authorised deductions including those of loans and advances to the employees coming under the purview of the Act and the extent of deductions from their monthly wages have been elaborately dealt with u/s 7 of the Act. The same thing is covered by section 18 of the yet to be implemented Code on Wages,2019. You may, please, go through it and ascertain for yourself.