1st of, because even I didn't know.
1. Make sure you subscribe to the creator of this mod, when you do it will automatically download in you're workshop.
2. go to steam apps, to do that you go to computer, then your disk, then program files (x86) > Steam > steamapps, then click on workshop and then content.
3. Copy the file you had downloaded from subscribing to the creator, Then you need to go to you're server files.
4.Go to Library in your steam game launcher, right click, then click properties, local files then browse local files.
5. Open up the server file, then the file you made for your server, open up work shop, content, Copy and paste it in there.

Now try restarting you're server, when you open up the command console, time in, ====> Example: Admin CaptinJacksparrow In The console, it must be you're STEAM ID and not you're Unturned ID.

Make sure to type in "SAVE" in the command console to save you're progress!

Now try typing in the command:
EXAMPLE Command:
*DO NOT WRITE IT LIKE THIS or you will be really dissapointed xD*
@vehicle CaptainJackSparrow/7102

Yet again, it must be a STEAM ID, not UNTURNED ID

Example, My Steam ID is People hate me
Unturned in Brokenswouls

My problem was, I kept typing in, Brokensouls when, I was suppose to type in "@vehicle People hate me/7102"

Try it! if you need help, I will do my best, hopefully though this should cover most of the problems.