I'm glad there's more free material online for optimization modeling and algorithms. Personally, here's my favorite list for algorithms and modeling for optimization:

For learning the simplex method, Linear Programming by Vasek Chvatal (first 10 chapters): https://books.google.com/books?id=DN20_tW_BV0C&printsec=fron...

For learning branch and bound, Integer Programming by Laurence A. Wolsey https://books.google.com/books?id=x7RvQgAACAAJ

For odd modeling tricks for integer programming, Logic and Integer Programming by Williams, H. Paul https://www.springer.com/us/book/9780387922799

For modeling tricks for convex programming, Convex Optimization by Stephen Boyd and Lieven Vandenberghe https://stanford.edu/~boyd/cvxbook/

For basic nonlinear optimization algorithms, Numerical Optimization by Nocedal, Jorge, Wright, S. https://www.springer.com/us/book/9780387303031

I've never really found the ultimate optimization book, but the references above tend to have the right modeling techniques, algorithms, and references. I've found they're a good place to get the right idea and the right words to search for more material.