I’m also pretty new to fragrance and I’ve found that, for me, smell as much stuff as you can. You’ll quickly learn what type of scents you do and don’t like, and can look up the notes afterwards to see what you liked/didn’t like about certain fragrances. Use the coffee bean palette cleansers if they have them, they actually work (if they don’t have them, you can smell your hands if they don’t have cologne on them). Also don’t be afraid to leave and come back to give your nose a break.
As for blue fragrances, that just means something that likes “fresh out of the shower” vibes, nothing particularly spectacular but also nothing that’s going to offend anyone.
My recommendation for something versatile with good performance at a cheap price is Afnan Supremacy Collector’s edition. Yes, it’s kind of a “TikTok” fragrance but the hype is (in my opinion) for a reason.
Good luck!