Meaning
The number two on a square keycap. It means two, second or a pair, and it is the usual second line in a numbered list.
It suits the second option in polls, the second step of a guide and anything about pairs or couples: “Table for 2️⃣ tonight, finally a date night” It is also a quick way to vote, by replying “2️⃣” to pick the second choice. Pair it with 👫 or 💑 for couples.