I have started my journey in coffee some years ago, and I can tell when I like coffee based on its flavour, texture, acidity but the only thing I cannot taste is sweetness. What do I need to look for?
I'm no expert and definitely don't have the most refined palate, but from what I've heard and experienced, comparative tasting is the best way to start to dig into and understand flavor.
For me, sweetness is a big one here. Since coffee isn't as sweet as a lot of other stuff we eat, having other coffees to benchmark against with more or less sweetness will help make it more noticeable.
Which i have done, and have tasted difference between two or three cups. But like I mentioned in my other comment, I might have experienced it in notes as vanilla or chocolate (which I personally associate to sweet) but I simply didn't know that what it was called sweet.