I want to install the Package Control. So I, after opening ST3, clicked on the "Tools" tab then on "Install Packages Control ...". The message asking me to open the Command Palette appeared. So I opened the latter, wrote "Install Packages Control" then hit Enter. Nothing knows past even while waiting a little. I then closed ST3 but opening it a second time , when I write "Install Packages Control" in the Command Palette nothing is displayed, as if it does not exist. In addition, the "Install Packages Control ..." line of the "Tools" tab has disappeared. So what to do?
And, (I don't know if it's used for something) I have Windows Vista T Home Premium Edition (yes, I know it's old)
It means your "packages control" is installed already. Now you can open your command plate (ctrl+shift+p) and type "Packages control:Install package". After clicking on it. You can install required packages you need.