Hi. Can i do this for every possible feature that build on selection of sound.
Can you try writing your questions in clearer English, please. Use more words.
The same selection area must be used for all tracks, but you can SHIFT-click on the Track Control Panels of each track (above the Mute / Solo buttons) to include or exclude that selection area in each track. See http://manual.audacityteam.org/o/man/faq_editing.html#selcopy .
You can apply effects to the selected audio in the selected tracks.
Are you going to reply to https://forum.audacityteam.org/t/sound-sliding/33104/1 ?
Gale