How can I stop my Mac from saving duplicate files on Pages?

every time i create a draft of my work in Pages or numbers or downloaded pdf (as bills) Macbook is been saving again EVERY TIME i need to take a look or editing . He ask save or delete and frustrated not to lose it i say save but hiz not replace it . I have hundreds of every document which is a real unconfort issue . i m stressed and dizzy . Any help ?

as you see in screeshot , in this document i corrected a doubel fulstop , i try to close window by clicking in red spot in the left upper side to close it. Or whether i click "save" system keep making new copy , making multiple copies every time you want just take a look .

[Edited by Moderator]

Original Title: avoid lose and multiple copies when you open a saved document