If an incompatible resource pack is detected, it will be marked in red. Not every resource pack works with every version of Minecraft. When you are done adding your resource packs, click the Upload button to begin the upload. The order of your resource packs can be changed using drag and drop. The higher up a resource pack is in the list, the higher its priority. It is also possible to combine multiple resource packs, just like it is in the Minecraft client. You can then select a resource pack file, or drag and drop resource packs into the resource pack list. To upload a server resource pack, click the Upload button next to the resource pack option on the Options page. Server resource packs allow you to automatically provide a custom resource pack for all players on your server.

In Minecraft, textures, sounds, and other elements of the game can be modified using resource packs. For more information about how to add resource packs to Minecraft Bedrock Edition servers, check out this article: Installing Addons (Minecraft Bedrock Edition) This article is about Minecraft Java Edition.