Can I replace the keyless entry remote of my car without replacing the whole alarm system?

I own a 2010 Ford Everest and my keyless entry remote is already giving up on me. I lost my spare. So can I replace it? Of yes, how?

You need a Ford dealer to get you a new remote unit and maybe you need a new battery in the one you have

Yes, you go buy a new one. A ford dealership parts counter is a good place to start. You do know there's a battery in the remote right?