who sang the above mentioned song?
Joe Cocker
Introduction
Due to the difficulty he faced in getting more than two of his compositions onto each Beatles album, Harrison first offered the song to Joe Cocker. 
who did george harrison wrote the song something for Pattie Boyd who was she? She is an English model and photographer.
Harrison The Beatles and George Harrison It is a song by the English rock band "The Beatles".
Something (Beatles song) Something (Beatles song) Something (Beatles song)
Background and inspiration Introduction Introduction
While Harrison imagined the composition in the style of Ray Charles, his  the Beatles, "Something" is a song by the English rock band the Beatles from their 1969 album "Abbey Road". 
wiki:389773
Something (Beatles song) [SEP] Introduction
While the single's commercial performance was lessened by this, it topped the "Billboard" Hot 100 in the United States as well as charts in Australia, Canada, New Zealand and West Germany, and peaked at number 4 in the UK. "Something" is described as a love song to Pattie Boyd, Harrison's first wife, although Harrison offered alternative sources of inspiration in later interviews. Due to the difficulty he faced in getting more than two of his compositions onto each Beatles album, Harrison first offered the song to Joe Cocker. As recorded by the Beatles, the track features a guitar solo that several music critics identify among Harrison's finest playing.