Egyptian hieroglyphics already had alphabetic elements, and the canaanites borrowed those: https://en.wikipedia.org/wiki/Egyptian_hieroglyphs (“Egyptian hieroglyphs are the ultimate ancestor of the Phoenician alphabet, the first widely adopted phonetic writing system”).
Egyptian heiroglyphs were not an alphabet, even if they had alphabetic elements (in addition to pictographic ones). Scholars generally agree that proto-Sinaitic was the first alphabet, and all subsequent alphabets used today are either direct descendants or directly inspired by it. https://en.wikipedia.org/wiki/History_of_the_alphabet
Protp-Sinaitic was an abjad not an alphabet.
As per the Wikipedia links, it's generally considered by scholars to be the origin of all alphabets and an early alphabetic script. Abjad is a term invented in 1990 to distinguish early alphabetic scripts without vowels from later scripts with them. Effectively every scholar agrees that Canaanite/Aramaic/Hebrew/Arabic are alphabetic systems (while also acknowledging them as abjads).