How to open an folder and resize it?

I added an actions to
1.open a folder
2.an action to resize it.

But there problem is that 2nd action is resizing currently opened window and not the newly opened finder window.

I suppose you're using AppleScript?

You can try something like this:

set targetFolder to ((path to documents folder) as text)
set targetBounds to {10, 10, 500, 500}
tell application "Finder"
  activate
  tell (make new Finder window to targetFolder) to set {bounds} to {targetBounds}
end tell