Go to the official Minecraft website or Microsoft account page
Sign in with the account linked to Minecraft
Open your profile or account settings
Find the Gamertag or profile name section
Select the option to change your name
Enter the new name you want
Save the changes
If you are on Java Edition, change your Minecraft profile name on the official Minecraft account page
If you are on Bedrock Edition, change your Xbox Gamertag through your Microsoft account
Wait for the name change to update in-game