About Difference between a resume and a cover letter
A cover letter is little bit different from a resume. There are tons of cover letter writing services, go for that if you are beginner. Or if you want to do it on your own, you can keep in mind that a resume only highlights your education and your career, while a cover letter is also called a letter of motivation. It describes the recruiter about your interests, professional background, and reason for applying etc. Hope it helps.