Yes, you should introduce yourself in a cover letter. Introduce yourself by stating your name, the position you’re applying for, and how you found it.
For example:
My name is Henry Applicant, and I’m applying for the open Account Manager position listed on LinkedIn.
While there are some other cover letter opening strategies, introducing yourself by name is the most professional way to begin a traditional cover letter.
Here’s an example of how to start your cover letter with a proper introduction: