Dear Bharathi,
Normally, the notice period will be fixed by the company in their offer of employment or in the HR policy of the company.
During the probation period, either party does not need to give any notice; they can separate by a simple letter to the other party.
After probation, up to 2 years of service, it may be 1 month for either party. After 2 years, you can fix the desirable notice period with your management, which will be served by either party deciding the separation.
For poor performance of the employee, the company can issue a show cause notice initially with 3 days to give an explanation. If the employee fails to submit a convincing reply, then a warning letter may be issued, followed by 15 days to show improvement in performance.
The next step can be a letter for poor performance, with a 1-month notice (either by pay or by service) and clearance form. Please issue the experience certificate/service certificate and due payments immediately within 7 days from the date of leaving the service. You can provide a PF Claim form or Transfer form with instructions to apply after 2 months.
I hope the corrections above align with your intended message. Let me know if you need further assistance.