"laden" without prefix usually does not mean "upload".
"To upload" is "hochladen" in German. "To download" is "herunterladen" or short "runterladen".
Because lädt is for third person singular. You would have to use laden with the formal Sie (was laden Sie/Sie laden was?) or lädst with du (was lädst du/du lädst was?)
couldn't it also be 'what is it loading' when the 'sie' is referring to 'die seite'?