Answer:
When writing a cover letter, you should:
introduce yourself
mention the job (or kind of job) you're applying for (or looking for)
show that your skills and experience match the skills and experience needed to do the job
encourage the reader to read your resume
finish with a call to action (for example, asking for an interview or a meeting).
Keep it short. A cover letter is meant to be a summary of your resume, so don’t write more than one page.