It’s perfectly ok to mix bits and pieces of other traditions in your work. In magical paths, this is called being an eclectic practitioner. The philosophical definition of eclecticism is denoting or belonging to a class of ancient philosophers who did not belong to a recognized school of thought but selected doctrines from various schools of thought.
As humans, we often find different thoughts or practices that appeal to us or the direction our path is going. It’s common to find people using the parts that sing to their souls and rejecting the parts that don’t. This is how magical practices evolve and there is nothing inherently wrong with being eclectic.
The second part of your question about cultural appropriation is really about ethics. Cultural appropriation vs. cultural appreciation lies with intent. There is an adage that claims all things are new again. Appreciation and eclecticism are ways of taking teachings and lore and using their influence to direct your path while still honoring their original intent. Cultural appreciation includes respect for the teachings and a firm understanding of the origins of the practices you are incorporating. If you use the 3 P’s (Power, Privilege, Profit) to determine your motives you can avoid appropriation which ends up dishonoring the original practice.