For Minecraft: Bedrock Edition, see Invite Friends to Your Minecraft: Bedrock Edition Realm.
After you create a Minecraft: Java Edition Realm, you can invite your friends through the Minecraft game menu.
Note: while you can invite as many players as you’d like to your Minecraft: Java Edition Realm, only 10 can be online simultaneously.
Invite friends through the game menu
- Select Minecraft Realms from the Minecraft launch screen.
- Select your Realm and then select the Configure button.
- Select Players and then select Invite Player.
- Enter the player's Java Profile Name and select the Invite Player button.
You can also sign into your profile on Minecraft.net and invite members from the Realms tab.
See these resources for more information about Minecraft: Java Edition Realms: