I can't say I'm really good at picking the perfect wine for dinner, but I try to be better at it. I often read articles on a wine portal like this one
https://thisdayinwinehistory.com/ . I like to learn more about this drink and in each article, in addition to information about wine, there is a lot of interesting things. I don't think it's possible to become an expert in wine through theory alone, but reading posts like this helps me get a better idea of what wine to try.