I've been on a Math journey since I retired a couple of years ago and I agree with all the books mentioned that I know and look forward to picking up some of the one I do not know. I agree baby Rudin is essential, but I find it tough going.

Some books I liked for self study because they have answers:

Introduction to Analysis, Mattock.

Elementary Differential Geometry, Pressley.

There is also recently Needham's Visual Differential Geometry and Forms, which is great.

Edit: I should also mention Topology without Tears (free, online, very good) https://www.topologywithouttears.net/