title: create a new data frame with columns from another data frame based on column names in R
body: <p>Data frame A exists. </p>
  
  <p>I want to create Data frame B and insert certain columns from data frame A in Data frame B. </p>
  
  <p>I do not want to use the column numbers but the column names to do that</p>
  
  <p>Thank you very much!!!!</p>