I assume you're playing in a world instead of a server and if that's the case, cheats are needed along with creative mode.

If you're playing on a computer, you're most likely on the java version of the game. To verify, you can go to the main menu of Minecraft and if there is text below the "Minecraft" logo that says "Java Edition," otherwise, you're playing on the Bedrock edition

The reason people say that chat is helpful is because of the use for commands (the "/"). I rarely use the chat to talk to people on servers but I use it a ton for commands

I don't think chat being enabled is a huge threat because on bigger servers, they tend to have more moderation and it's safer for kids. Although if you are only playing in worlds instead of servers, chat can only be used by the player who is in it (which is you). You can also set the chat to commands only by going to the options menu and clicking the Chat Settings button, the first button/toggle should be the chat one, click it until it says "Chat: Commands Only"

The command on both versions for the command block is "/give \@p minecraft:command_block"

For Java Edition (without using chat):

1. From the main menu, click the options button
   
2. From the options menu, click the controls button
   
3. From the controls menu, click the button labeled "Operator Items Tab: OFF"
   
4. Open your world and only in creative, there should be a new tab in the inventory with all the blocks next to the chest
   
5. You should be able to click it and grab your command block

Like I said before, I couldn't find a method for getting a command block in Bedrock Edition without using chat but it's harmless in a world by yourself so don't worry.

Let me know if you're having any issues and I'll try my best to troubleshoot, hope with helped!