Below, you can find a few resources to learn more about typography.
Butterick's Practical Typography by Matthew Butterick (free)
A good place to start for beginners; as the name implies, this is a very practical overview and gets very detailed in parts.
Professional Web Typography by Donny Truong
Specific to web type; includes some technical-leaning material about code.
Thinking with Type by Ellen Lupton
A book with a good overview of the history and use of typography; a lot of pictures of examples.
The Elements of Typographic Style by Robert Bringhurst
A very detailed cannon of typography; this one is not good for beginners but designers consider it to be the Bible of type style