Problem with the Legendary Texture Pack (Bedrock)

Hi and thanks for reaching Xbox gamer's community. My name is Josef.
Thanks for reaching out! I'm an Independent Advisor and a Microsoft user like you.
I'll be happy to assist you out today.

Hope you're doing great today Regz

For this specific issues with Minecraft the best option is contact Mojang support via link below:
https://help.minecraft.net/hc/en-us/requests/new

Thank you for contact us! I'm Anderson, an Independent Consultant and a Microsoft user like you.

Good evening

Download a texture pack (also known as a resource pack) in a compatible format such as .mcpack or .zip from a trusted source. Make sure the pack is designed for Minecraft Bedrock Edition.

Open the downloaded texture pack file. It should automatically open with Minecraft Bedrock if you have the game installed.

Minecraft Bedrock will import the texture pack and prompt you to apply it. Click the "Apply" or "Activate" button to enable the texture pack.

If the texture pack doesn't automatically open with Minecraft, you can manually import it. Copy or move the downloaded .mcpack or .zip file to the following location on your mobile device:

Android: Internal Storage/games/com.mojang/resource_packs

iOS: On iOS devices, the process requires a file management app like Documents by Readdle or iExplorer. Move the texture pack file to the "games/com.mojang/resource_packs" directory.

After moving the file, open Minecraft Bedrock and go to "Settings" > "Global Resources."

In the "My Packs" section, you should see the imported texture pack listed. Tap on it to activate it.

I am having this problem on Pc and it is the Bedrock edition. And yes i am having the same issue with other texture packs that I have tried downloading

Some texture packs was not transfered from 360 edition to the newer Bedrock edition.

you need to go to the store, texture packs then search bedrock pack or something like that and download it (its free) and then you’ll be able to sign in!