When you are just starting out in the hobby of metal detecting there is a lot to learn. There will be information flying at you from just about every direction and you will need to learn to filter it. That is why I always suggest that you start out your journey with some metal detecting books.
For someone like me, there is nothing like a good book. They offer so much information that other venues cannot offer. However, not everyone feels that same way. There are many who prefer digital methods over a paper book. Either way, there is nothing wrong with some reading to get you started on your journey.
There are a lot of great books on metal detecting out there. For the early reference I would suggest you find anything written by Charles Garrett, the founder of Garrett metal detectors. He has written extensively on the subject and has covered just about every possible sub-topic in the hobby.
Beyond those, you can get even more specialized. There are dozens of titles that are considered to be the best of the best in metal detecting books. They are insightful and witty at times. They will all help you get out there in the field and digging the best you can.
Happy Metal Detecting