1. To see the last commands for your username:
history introduce words from the history list into the input stream, making it easy to repeat commands, insert the arguments to a previous command into the current input line, or fix errors in previous commands quickly.
it saves the last x commands in a file called .bash_history (it's hidden, so you need to ls -al to see it) and is located in your home directory.
2. To move through the last commands:
you can move through the last input commands, by using:
a. up/down arrow keys - up is for previous and down is for next
b. ^p (CTRL+P) and ^n (CTRL+N) stands for previous and next
yes, there is an input autocomplete in CLI. the magic key is TAB. you can use it by typing the first letters of a command or a file, then press TAB and it will complete your command or file.
to move to /var/www/ directory:
a. type cd /v and press TAB. you will have now cd /var/
b. type b and press TAB. you will have now cd /var/www/
4. sudo bang-bang:
as described in one of the previous tutorial, you can use the sudo !! command to have permission over a command, which you wrote without the sudo in front.
let's say your command was nano /var/www/index.php and your not the owner. you will receive a text, telling you that you don't have permissions to access that file. now you can enter sudo !! command.
this command is very usefull when you wanna find a past command. Just press ^r (CTRL+R) and start typing part of a command and you will see the suggestions.