Others are going to chime in with answers to the questions you asked in your OP. I'd just like you to know, lingerie is for you first and foremost. Your comfort and self-rewarded desire to wear (or not wear) any particular garment is priority #1! There's a lot of cultural and marketing brainwashing that programs us to believe that lingerie is for the sexual gratification of men. This is absolutely not true.
I really recommend Cora Harrington's In Intimate Detail. It's an exquisite introduction to how lingerie can serve as a tool to be developed alongside discovering ones personal identity. The book achieves this while also performing as a delightful introduction to many of the logistics of lingerie. Names, pictures, purposes.
Did I mention it has the cutest of pictures?!?