Simple: he had gone to God to get permission.
Satan has no freedom to just do things to people or Creation, according to Job; he has to go make application to the Most High and get explicit permission.
Jesus was playing along with Satan’s ‘fishing expedition’. Each challenge Satan posed was an attempt to get Jesus to either abandon course or reveal crucial information, and in each response Jesus deftly turned aside both.
So “given the power” is right to the point: we know from Job that Satan can’t do a thing without getting permission from God first, and in the temptation narrative we see that God allowed just enough to leave Satan puzzled and probably with some very wrong ideas about what was going on.
But twisting the text is the only way to get from Satan having to ask God for permission to bother one of God’s people to Satan being able to run around freely perpetrating mass deception on humanity.
Nothing in the text anywhere suggests that Satan can be in more than one place, let alone orchestrate massive changes to God’s Creation in order to deceive us – or that God would go along if Satan wanted to do so!
The mess comes from the fact that you are operating under the misconception that science has anything to do with the scriptures, or more broadly that the Old Testament can be read as though it was written under a modern worldview.