Anyone knows some tool than can mock/mimick different type of servers/protocols so I can train my backend network programming skills easily?

Stupid question incoming. If one dev that hasn't studied the field (I'm talking about me obviously, a Java backend dev with professional experience) wanted to enter this AI engineering field, specifically for computer vision, does he have to learn machine learning when computer vision is mostly about deep learning?
Same question for algebra? Are there knowledge barriers (except for programing skill ofc) is my question for someone who's in tech but not into anything related to these