What makes you think you can't join? In Java, there are no bundled servers that ship with Minecraft so you have to go out on the internet and find their addresses, type that stuff in, do whatever whitelist application stuff they require you to do, and then log into the world.
Minecraft doesn't have official servers, only server software you can use called Realms to create your own (if you pay) and setup a world players can join. You can join a world if that admin owns the Realm and you don't have Realms. Otherwise players set in to setup their own servers or large server groups like those that setup minigame servers. With minigame ones you mostly just need the IP address or otherwise and your good to join. Just like with anything don't cause trouble (use xray, bother other players, ruin the server, etc) and play the game with an official account with a bought version of the game.
While official servers would be nice I think it would be as toxic as other games (otherwise Mojang at least giving people Realms to manage and do what the community wants allows for more to be done and for server admins to do things, the server commands do a good job and otherwise Bukkit, Spigot and otherwise allow for more options so Mojang doesn't really have to jump in even though they could but with the updates and otherwise they are doing fine) so the way the community has gone about things to setup their own servers, works well. Otherwise play LAN with a friend/group if you aren't up for servers or can't join any but still want to play the game.
Why can't you join any servers
What makes you think you can't join? In Java, there are no bundled servers that ship with Minecraft so you have to go out on the internet and find their addresses, type that stuff in, do whatever whitelist application stuff they require you to do, and then log into the world.
If you want a server to join try here where they are advertised (for Java, if you want Console/Bedrock Edition then go to the threads where many post there): https://www.minecraftforum.net/forums/servers-java-edition
Go through the questioning of 'what type of player are you, what's your past server experience and more'.
Otherwise there is the 'I want a person to play with' thread here: https://www.minecraftforum.net/forums/minecraft-java-edition/survival-mode/2485318-need-a-friend-to-play-minecraft-with-click-here?page=185
Minecraft doesn't have official servers, only server software you can use called Realms to create your own (if you pay) and setup a world players can join. You can join a world if that admin owns the Realm and you don't have Realms. Otherwise players set in to setup their own servers or large server groups like those that setup minigame servers. With minigame ones you mostly just need the IP address or otherwise and your good to join. Just like with anything don't cause trouble (use xray, bother other players, ruin the server, etc) and play the game with an official account with a bought version of the game.
While official servers would be nice I think it would be as toxic as other games (otherwise Mojang at least giving people Realms to manage and do what the community wants allows for more to be done and for server admins to do things, the server commands do a good job and otherwise Bukkit, Spigot and otherwise allow for more options so Mojang doesn't really have to jump in even though they could but with the updates and otherwise they are doing fine) so the way the community has gone about things to setup their own servers, works well. Otherwise play LAN with a friend/group if you aren't up for servers or can't join any but still want to play the game.
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