All practical scripts have a bibliography section, where bibliographic resources are detailed (they are all on the Internet and are free to access), as well as YouTube videos that can be very clarifying on specific topics of the subject.
You can also use (in fact, it's quite convenient) artificial intelligence (AI) resources as help to solve doubts of the subject. For example, looking for substance properties, theoretical explanations of transport phenomena concepts, calculation procedures, etc.

When you use AI resources you need to indicate it, as if it were a bibliography and, above all, check the information given by the AI system... you think that these systems, if they don't know something, they invent it... therefore, you should not rely on it uncritically.