How do i write an application letter to a supermarket

Start with a reference to how you find out about this job, refer to the website, paper, and date;
Make a proper introduction to yourself and your personality. A formal but friendly intonation is important;
Quantify an example of your education and working experience;
Emphasize your skills, that are mentioned in the job description;
Provide a key lesson learned, for example: that smiling is a key to pleasing the customers when being a cashier;
Use definitions and wording from the original job posting in cover letter and resume.
Regarding the structure of a model letter or email:

The first paragraph is an introduction of yourself and how you learned of the opening, as well as your interest in the position/organization. This requires you to relate yourself to the organization or to the position in order to demonstrate your interest.
The middle paragraph(s) is a profile of how your skills and experience match the qualifications sought. In order to construct this profile, be sure to read the job description carefully to get a clear idea of what the company is looking for. This goes beyond just the “qualifications” section of a job description. Make sure to discuss your ability to do the job.
Review the company website and other materials to learn what type of person the company might value. Match your experience and education (academics, volunteer experience, etc).
Below you can download a sample cover letter for the supermarket.

Dear [Manager function and name],
I am writing to you because I would like to apply for a job in your [Job location]. I have shelf filling experience in my local newspaper shop but I need something more suitable and regular due to me starting my family soon. My responsibilities were to refill the shelves and to make sure of any deliveries so that there was someone who knows what the shop needed. I live very close to the supermarket so I am able to walk and I am able to get there in minutes if you need someone to cover someone else’s shift quickly. I am a hard worker very determined to show people what I can do and prove myself.

I can work anytime for however long. You will find attached my full CV with all of my contact details. If you have any questions or want to talk with me don’t hesitate to call. I hope that you will consider me and I look forward to hearing back from you.

Yours sincerely

[Your name]