In Debian, you can install Midnight Commander using the system package manager:

sudo apt install mc

Run mc to invoke Midnight Commander.

mc

When you first launch, you'll have two panes. Press tab to switch between the two panes. At the bottom of the screen there will be a shell. Each pane has its own shell tied to it. When you press tab to switch panes, it will switch the shell you are in. Press CTRL-o to toggle the shell full-screen.

Navigate up and down with CTRL-n and CTRL-p and use ENTER to open a file/directory.

To copy a file from one pane to the other press ALT-5 (refer to the legend on the bottom of the screen.)

To connect to a remote server using SSH and transfer files, use cd and provide the appropriate. For example:

# For SSH (File transfer over SSH aka FISH)
cd sh://dano@devdugeon.com:22/home/dano
 
# For SFTP
cd sftp://dano@devdungeon.com
 
# For FTP
cd ftp://dano@devdungeon.com

Alternatively, you can use the top menu and choose the “Left” or “Right” menu and select FTP link, SFTP lin, or Shell link to jump to a directory.