On Mobile Devices (Android/iOS): Open the .mcpack file using a file manager or directly through the browser. Minecraft will launch and start importing the pack.
How to activate:Launch Minecraft and go to Settings > Global Resources, or edit a specific world and go to Resource Packs.
Under Available Packs, select your installed pack and click Activate.
Once active, you can reorder the stack to control which pack takes priority.
Return to the game, and your texture pack will be applied.
Now test in game!
On bedrock just open the mc file then minecraft should make it a pack in in game!