Hi New-To-It!
I am also relatively new, to collectible beads, but spent many years with my first love, stone beads. My overall advice is to first, join a local bead society if there is one to be had. The members will have a wealth of diverse experience and information to share.

Second, there is no substitute to spending a lot of "face time" with beads. When I was starting out with stone beads, I went to a LOT of shows and spent a long time looking and asking questions. You will have to keep an open mind and accumulate experience and information to apply to your own collection. There is a lot of "suspect" information out there, and it takes patience to get good at something like identifying all the varieties of turquoise, which is a good material to start with because there are so many, as well as so many imitations.

When buying, I decided early on to only make "significant" purchases from sellers that I knew personally, or was referred to by someone I knew. An example would be buying an authentic antique Tibetan piece such as what you mentioned. I would hesitate to buy something like that unless I was really comfortable with the reputation of the seller, since I would not be able to tell the authenticity myself.

For learning more about turquoise, you could start by purchasing a range of turquoise "products" from a dealer like Fire Mountain, so you have examples on hand to compare to other beads as you browse the bead racks at shows.

And of course, this forum is a great place to post questions, although there are limits to what can be determined from photos.

Good luck with your beads and above all, have FUN!