Bright Side of Maths for sure. Also, there are several universities that post full lectures from their academic coursework on YouTube. E.g. here's what Invidious brings up when I search for "analysis lecture". I strongly advise doing a real analysis course as soon as possible. (The "real" in "real analysis" pertains to the real numbers, i.e. it does not imply the existence of "fake" analysis courses, i.e. it's not an epithet.)
Really, real and complex analysis should be part of the electrical engineering curriculum IMO, but I'm biased as an EE grad student who is disappointed at there not being enough math 😆
Also I would be remiss not to mention that Library Genesis and Anna's Archive exist and are not unique (see Open SLUM for mirrors and their status). You can find almost any STEM textbook on these sites for free. Take as much as you can before the capitalists destroy this incredible resource. IMO videos are the most fun way to learn math, but books are by far the most efficient.