For my CS degree, the two classes that were most useful foundations-wise were:

1. Learning how to prove things with math

2. "Baby compilers" machine code, building an assembler, building a simple MIPS compiler, regular expressions, parsing, etc

There's a lot of other topics but those two really set the foundation. All algorithms class and data structures are best understood with a mathematical intuition. Not to mention you want to go into VR, lin alg might help you.

YMMV. Lots of great programmers don't have a math background, but for me that helped.

The CLRS book is pretty standard (but mathy).

You'll learn things as you work too so don't discount patience.