I was simply trying to explain how a previously offered suggestion works, since you said that you did not understand that. I could repeat that advice, but you might still not get it: your script should not print the headers until it has looked at the cgi parameters, done a database lookup, and figured out whether or not it needs to redirect; if redirection is needed, just do that instead of printing headers; otherwise, print the headers and do whatever else is needed.

So to be exact, my suggestion is to use the advice already given, and if you still cannot understand that, maybe you should be looking for different work. Just as some people are tone-deaf and should not try to sing, so perhaps some people just cannot figure out web/cgi programming, and shouldn't try to do that.