You have just been offered a good job and you have accepted it verbally. You may still want to formally accept the job. In such situations you can write an acceptance letter. Here is a sample acceptance letter. You can draft your own acceptance letters using this as an outline.
Sample acceptance letter
City, State, Pin code
March 4, 2020
Dear (Recipient Name):
I am delighted to accept your offer of employment as a sales manager with Lotus Corporation, starting on March 20, 2012. The position sounds quite challenging and that is exactly what I am looking for.
I have reviewed the terms and conditions specified in the offer letter. I have also signed and enclosed a copy of the offer letter as requested. If there are any other formalities that I need to complete before I can join the company, please let me know.
I look forward to working with you.
Enclosure: signed copy of offer letter