Supposing you have at least high school mathematics under the belt: 1. Book of Proof by Hammack [1] 2. Tom Apostol Calculus Vol 1 (stop at Linear Algebra) 3. Linear Algebra by Insel, Spence & Friedberg 4. Understanding Analysis by Stephen Abbott 5. Tom Apostol Calculus Vol 2 These are books with excellent exposition, and solution manuals are available when needed. You are absolutely required to do all the exercises. To learn mathematics is to do mathematics. Two other excellent books are Spivak - Calculus, the problems in this book are very good, but much more difficult than Apostol. For more advanced analysis there's Walter Rudin's Principles of Mathematical Analysis (baby Rudin), which on its own is too difficult as a first exposure to analysis, but there's a cool professor that recorded an entire semester of baby Rudin lecture videos [2]. This is as close as it gets without being enrolled in a university. [1] https://www.people.vcu.edu/~rhammack/BookOfProof/ [2] https://www.youtube.com/watch?v=ab41LEw9oiI&list=PLun8-Z_lTk... (https://www.youtube.com/watch?v=ab41LEw9oiI&list=PLun8-Z_lTkC6qJF1sVh3_Hx7aL6FPd0IN) (the first video is a bit blurry, it gets better)
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