The constellations gemini is only visible from Earth for several months of the year because

Because the earth rotates around the sun every couple of months so you wouldn't be able to see it for the entire year.

Gemini is best seen through the months of January to May. It is known to be one of the most brightly lit constellations, having two very bright stars Castor and Pollux. January and February are the months where Gemini is at its highest in the sky. After May, Gemini falls low in the west-northwest region of the sky, making it less visible.

I did the same thing.