One 18 ft x 24 ft tile will be more than enough. Since the measurement units used for the tile are not specified, I have assumed that they are the same as the only units that are mentioned in the question.
210 tiles
Ceiling tiles are not all the same size, but I have often seen them in the size one foot by one foot.
16 square tiles
You would need a total of 36 tiles to cover that area.
That would depend on the size of the tiles.
210 tiles
Your question is confusing because you are using two different scales. If your room is 10 ft x 12 ft and the tiles are 2 ft x 2 ft, the answer is 30 tiles.
Ceiling tiles are not all the same size, but I have often seen them in the size one foot by one foot.
You will need 233 30x30cm tiles to cover the room.
The answer will depend on the size of the tiles!
123 tiles
16 square tiles
You would need a total of 36 tiles to cover that area.
Depending on which type of ceiling panel, there are several benefits. Radiant ceiling tiles are an economic heating alternative. Suspended ceiling tiles enhance a room's appearance and provide sound insulation. Acoustic ceiling panels provide further sound control.
13 boxes with 13 tiles in each
That would depend on the size of the tiles.
I assume you mean an 8ft x 6ft room, which is 48ft2. I assume you mean 12in x 12in tiles, which are 1ft2 tiles. I don't know how many tiles are in a box, but you would need 48 12in x 12in tiles.