Where silikon valley is situated?

Answer 1

I presume you mean Silicon Valley?

Silicon Valley is the southern part of the San Francisco Bay Area in Northern California in the United States. The region is home to many of the world's largest technology corporations as well as thousands of small startups.[1] The term originally referred to the region's large number of silicon chip innovators and manufacturers, but eventually came to refer to all the high-tech businesses in the area; it is now generally used as a metonym for the American high-tech sector.