Moses couldn't help himself, he was a foster child raised in the House of the Pharaoh, treated like a son, but at some time he found out he could not succeed his surrogate father and be Pharaoh. When he coveted this power and started planning his deceit is not revealed by his scribes rather truncated biography. That he was treated like a son is revealed by his possession of a "staff" that was reserved for the House of the Pharaoh, ordinary priests and selected officials had lesser staffs.
As a trusted member of the House of the Pharaoh he had authority over matters that could not be questioned by lesser officials, thus he could move freely amongst the Israelites and plan a departure. There seems to have been some kind of exodus, but there was more to it than stealing gold and silver. What was taught to the male members of the House of the Pharaoh doesn't seem to be revealed anywhere, and therein probably lay the basis for Moses ability to manipulate the Israelites.