a friend gave me sea of thieves with a redeem code but it doesnt show up in the store

It'll actually just show up in your downloads under the Sea of Thieves game. No codes. Got to My Games and Apps, then Sea of Thieves, hit manage game and it should be ready to install.

If you preordered digitally through Xbox, you won't receive a code. You would already be able to download it. It would either show up in your ready to install area or you'll need to search for it in the store.

If you preordered it from a retailer, you'll need to contact the retailer you purchased it from for assistance.

I pre ordered online and I installed the pre order Sea of Thieves AND the pre ordered Sea of Thieves Closed beta. I have two Sea of Thieves in my Games folder now on Xbox One...and neither of them will let me in to the closed beta which started at 4am PST.
So I assumed you needed a code, which I don't have.

Hey matus0405,

By watching the Inside Xbox - X018 show on Mixer, you were eligible for a chance to receive a MixPot that included an exclusive custom "Forza Horizon 4 Limited Edition Festival Tee” top, Sea of Thieves Obsidian
Drum, and the Sea of Thieves Obsidian Spyglass.

To redeem this content:

• You will need to make sure this shirt content is installed in the "Manage Add Ons" section for Forza in the "My Games and Apps" section before you boot up Forza Horizon 4 or Sea of Thieves. Once in game, head to your character customization screen, and
  it will be available in the "Tops" section.
• Sea of Thieves add on will show up in game.

With that said, if you watched this event back on Nov 10th and never received these items, please let me know and I will be more than happy to look into this for you!

At least yours shows you own it in order history.. I had a full code that "redeemed" on March 18, but yet nothing in game and on order history it only shows Sea of Thieves, nothing for PSO2. I was able to return to the perk block before they removed
it and it kept saying I had already redeemed the content.

It doesnt show anything in my order history, but I go to Microsoft store and click redeem code and that's where it says redeemed.