Yes, one can learn from online available sources. I had Calculus I in school and then I found Prof. Gilbert Strang, MIT OpenCourseWare. [0]

openstax.org has a lot of good books. [1]

[0] https://www.youtube.com/playlist?list=PL49CF3715CB9EF31D [1] https://openstax.org/subjects/math

edit: i am an autodidact who loves to learn.