Hi!
@nicole0612 made a great suggestion to check out the "other brand" thread. It has a lot of great suggestions and ideas.
What I did when I first started out was to stare at the collections at Tiffany. Tiffany is very broad and has a bit of many styles of jewelry. Yet because they are organized by collection, it is very easy to learn and see what jewelry styles you like. This was really helpful vs. googling everywhere.
I would suggest the following...
First, browse by collection. You will be able to see the style and all the pieces. You will definitely know by looking at a collection, if you like it, love it, or hate it. My thoughts on a few collections are (these are my words here, not official Tiffany):
HardWear - Edgey and bold
Victoria - Classic and feminine
Elsa Peretti - Flowing and sensual (all of her pieces have a soft flowing edge, no hard edges)
Atlas - Industrial and crisp
T - Logo and clean
Schlumberger - Nature and Colorful
Soleste - Classic and Glamorous
Don't judge it based on the metal. Look at the design. Look also how the look changes when the metal changes (e.g. RG/YG/WG/plat). You get the idea. By doing this, you'll start to know what you like.
But wait, there's more! That's just the first homework assignment!

Now that you are familiar with styles, you need to look at pieces from another point of view, by category only, not by collection.
Part two... the second homework assignment...
Go back to the website and sort by category (e.g. ring, necklace, pendant, bracelet). Look at the pieces and see what you like, love, hate. It may surprise you that a collection you hated, you now love a ring because now you see it from a different perspective, compared to other rings.
For me, I really like to stare at the entire collection, then look at an individual piece by category. It really helps to absorb that piece as it was meant to be in a collection and also worn alone, to help with the "look."
I hope this was helpful. Now.. on to homework!

Update: I also want to add, you may not like the Tiffany brand, but that’s not the point. The idea is to see the styles you like. You can also pretend what would you choose if Tiffany gave you one free piece! Or two! What would you pick?!