Learn French: Range ta chambre maintenant.

Normally, the tu form of regular verbs ending in -er has an -s at the end (like tu ranges). But here is the golden rule for commands: regular -er verbs drop that final -s in the tu form. So, it becomes simply Range.

Where is the word for 'you' in this sentence?

Just like in English, French drops the subject pronoun (like tu or vous) when giving a command. The verb Range is already in the tu form, so the listener knows you are telling them to do it.

Why use ta instead of ton for 'your'?

In French, possessive words have to match the gender of the object being owned, not the owner. Since chambre (bedroom) is a feminine noun, you must use the feminine form ta.

Is ranger the exact same as cleaning?

Not quite! Ranger specifically means to tidy up, to organize, or to put away. If you want to talk about physically washing or scrubbing a room, you would use a different verb, like nettoyer (to clean).