There are various “introduction to the orchestra” sites around, and I remember seeing some videos that present the instruments and their limitations and capabilities, but can’t remember where off the top of my head… Did a quick search, and found one that seems to briefly explain the typical roles of the instruments:
Beyond that, the general recommendation is pretty much to learn from the masters (past and present) by listening analytically, and (when given the option) reading the scores. Basically, whenever you hear something interesting, try to reverse engineer it! Figure out how and why it works, and how it’s done.
That said, I believe one should be careful not to get stuck in “best practices,” and instead learn to analyze and understand the actual sounds and behaviors of the instruments, and how they work together in terms of “layering.” The has the advantage of also being applicable to unusual ensembles, synths, sound design, mixing etc, which makes it easier to bring in interesting timbres, and actually make them work in context.