are the members of this club and the previous group different?
No
S Club 3
S Club Live (also known as S Club Party; formerly known as S Club 3 and SC3) are an English spin-off pop group based in London with S Club 7 former members. 
what does the s in s club mean A theory is that the group is so-named because "S" is the first letter of the word "seven". what exactly is this club? An English pop group who are the members? Bradley McIntosh, Hannah Spearritt, Jo O'Meara, Jon Lee, Paul Cattermole, Rachel Stevens and Tina Barrett. was first one a part of any other group? Yes, he has been a member of spin-off group S Club 3
wiki:14292764
S Club 3 [SEP] Introduction
S Club Live (also known as S Club Party; formerly known as S Club 3 and SC3) are an English spin-off pop group based in London with S Club 7 former members. Originally, the group was founded by Bradley McIntosh, Jo O'Meara and Paul Cattermole. In February 2014 Tina Barrett joined them, but in May 2015, Cattermole left the group after the S Club 7 reunion. in August 2020, O'Meara tweeted that she had left the group to fully focus on an upcoming album and her solo career, thanking her fans for their support throughout the years from S Club 7 to S Club 3.