Agreeing that nothing can substitute for reading, but I'll offer one other resource. One of the things that makes writing romance so complex is that there must be 2 storylines happening at the same time AND working together. There's the external plot and the romance plot, both equally important. You're going for a similar thing, substituting romantIC for romance, so maybe they're not quite equal time, but it's a similar challenge. Gwen Hayes's Romancing the Beat is a short primer on how to weave plot and romance together (including ways to think about characters and how they interact). It's very trope-focused, so you'll have to decide what to take on and what to ignore, but it may help you recognize what's happening while you read, and may help you understand how to weave in the romantic thread of the story.