Reading the prompt
Before you type anything, the shows you a — a little bit of text ending in a symbol, waiting for input. It might look like this:
mini@laptop ~/projects/my-app $
Reading left to right, that tells you: your username (mini), your computer (laptop), where you currently are (the folder ~/projects/my-app), and then a $ meaning "your turn." The ~ is shorthand for your home folder. The symbol at the end is often $ or %; sometimes >. Don't type the symbol — it's just the shell saying it's ready.
This matters more than it looks. Most command-line confusion comes from not knowing where you are. The prompt tells you, every single time.