Answer me this question according to your experience: in order to learn the meaning of kanji compounds is better to learn separately the meaning of each kanji or learn them as one?
I would focus more on words (compounds) than kanji. You risk spending excess time memorizing esoteric pronunciations that are rarely used if you focus on individual kanji.
I think they go hand in hand - two sides of the same coin. Take a little time to learn about the kanji part of which is learning a bit about how it's used including vocabulary.
Learning the compounds is important because it gives you some real/practical context for your brain to grab onto.
But learning the kanji in isolation is also important because as you get into the language, attempting to understand texts from a wide range of contexts, you'll undoubtedly see the kanji used in compounds that you don't know. If you know the kanji, you can read words you've never been taught - and this means your actually literate in Japanese (that's what we all want to achieve).