I tried to translate your post, but I did not understand well.
If you speak in english or in portuguese, I can try to help you.
Regards.
Using and setting up a parameter and its value.
ZQuery1.ParamByName('someparam').Value:='somevalue';
ZQuery1.Close;
ZQuery1.SQL.Clear;
ZQuery1.SQL.Add('select * from sometable where somefield=:someparam');
ZQuery1.Open; //to use SQL commands that do not have results (like insert, update, delete), use ZQuery1.ExecSQL;