How do I enable command blocks on Bedrock 1.16.40 on server?

REVISED:

How to obtain command line in Bedrock on Aternos (which also lets you of course, create command_blocks)

1. In the options tab, enable White List and Allow Cheats

2 In the players tab, click Whitelist option and add your minecraft game name

2. In the players tab, click the OP option and add your minecraft game name.

3. In the files tab, click the Server.Properties file (You need to have already generated a world or uploaded a working world. Note: Official MineCraft Store World Templates do not work on Anteros)

5. In the Server.Properties window, make sure that Cheats and Whitelist are enabled.

Then scroll down until you see - Default player permission level

Change the Default Player Permission Level to Operator

6. Go to the Server tab and start your server and enter your world on Minecraft like normal.

7. Once in Minecraft you will have normal command line options available, along with server commands that you do not normally see in Minecraft.

8. Once in the game, use the command_line (aka the back-slash / ) and set the game mode via a game mode command to either Survival, Adventure, Spectator, or Creative. You will retain your OP and Command Lines regardless of which game mode you choose.

9. To give yourself a command block. Enter the command_line area of the game (chat box with a back slash) and use your full name when entering the command.

/give yourowngamename command_block

and then press enter. You can also give yourself up to 5 blocks by adding a 5 at the end.

/give SkyThrusters command_block 5

If you prefer video steps - I've added them to YouTube.

https://youtu.be/Eaid5xKMXL0