You can't. They will not give you permission. Tie-in novels are always commissioned from established authors and as it happened the owners of the NOES franchise have already commissioned such novels and released them ages ago (see below), so even if there was any chance of them giving a 17 year old unknown writer permission to write a book, they already have a contract with somebody else.
What you wrote is a fanfiction. You can publish it on fanfiction.net on a purely non-profit basis.
EDIT: also I'm not sure if ricktechguy misspoke or is grossly misinformed, but almost none of his information is correct. You need to be very careful to take anybody's word. Always do a lot of research before considering publishing (Absolute Write below is a good place to start)
- Changing the title won't be enough to make sure you can't get accused of copyright infringement. With movie studios you have to be even more careful. The second you mentioned the knives on his hand, the hat and the green and red striped sweater, they'll know you're talking about Freddy even if you call him Mark and they'll sue. You'd have to change a lot more than just the title and names for it to be a stand alone novel.
- While ebook is the least costly self-publishing option, it is not the least costly publishing option. Rsearch publishing options thoroughly. There's three main ones: self-publishing where you get your books printed and do the rest of the work yourself, Vanity presses who print them, do a few extra services for outrageous prices and then pretty much abandon you to market them yourself and commercial publishing. The first two are non-selective. They accept anybody who pays to have their book printed but the chances you'll actually sell a lot of books are next to zero if you are not a professional business person yourself who is able to deal with marketing and distribution on a large scale. They also do not count as publishing credits with any of the professional writers' guilds - which basically means they won't consider you a real published writer. That's due to the "non-selective" thing. I can have my cat walk over my keyboard, pay them and print my book too. With commercial publishing on the other hand, they pay you. If they accept your book, it's because they have carefully chosen it from a pile of a thousand other manuscripts because they actually believe it will sell.