I want to know the passive voice of this sentence "𝐓𝐞𝐥𝐥 𝐡𝐢𝐦 𝐭𝐨 𝐥𝐞𝐚𝐯𝐞 𝐭𝐡𝐞 𝐫𝐨𝐨𝐦".
Your sentence actually contains two imperatives:
- Tell him
- Leave the room
The passive voice of these two commands in isolation would be:
- Let him be told
- Let the room be left
However, your original sentence is an active command to deliver a message to somebody else in the active voice. To change this sentence to passive voice, you need only to change the imperative that is directed at the hearer, so the answer to your question would be:
Let him be told to leave the room.
However, you could also passively request someone deliver a message in the passive voice. If you wanted to change both to passive, then it would be:
Let him be told that the room must be left.