can i put level codes like K#SVX7VBBYK

You can try out this code but be aware that many passwords on the web from other platforms don't work.
Also be aware that single player passwords don't work for multiplayer and vice versa.

At the end of each world (every 4 levels) you get a Password which contains the characters, lives and how much money they are upgrades are worth so those passwords are not just level codes.