This is super important. I'd argue that a huge part of learning to process feelings healthily is being and able to tell the difference between how one feels (which is an involuntary reaction that isn't controllable) and the actions taken as a result of that feeling (which require explicit choice to take). It seems obvious in the abstract, but I think it's almost a universal human condition for the line between them to get blurred. People will often say something like "I'm sorry I got mad" as if being angry is something that can be controlled, when what they should instead be apologizing for is the actions they took while mad (e.g. "I'm sorry for yelling"). There's a reason that "anger management" is a known term rather than "anger prevention", after all. If someone asks why you did something, "because I was mad" is not a healthy explanation; it removes your choice from the equation and paints yourself as a helpless victim of your emotions rather than someone with agency and the ability to act better even in the face of extinuating circumstances.

While it might seem like these are just linguistic quibbles, I've seen so many cases of people genuinely thinking that trying to suppress their emotions is the correct way to handle tough situations, and I don't think that ever works well in the long run. At most, it's sometimes beneficial to avoid expressing strong negative emotions immediately in certain situations, but that's only a short term tradeoff to avoid exacerbating whatever is currently going on, not a long term solution to avoid consequences of taking actions under the duress of heavy emotions. I believe that people would learn to act better by mentally framing their emotions separately from their choices and allowing themselves to feel them fully and ideally express them in a healthy way. Venting to a sympathetic family member or friend can be a good way of doing this, but that's also why therapy is something that would be benefit pretty much everyone in my opinion; having a trained, neutral professional to be able to talk through emotions without having to worry about overburdening them or worrying about having to interact with them in any other part of life is hard to beat in terms of a strategy for dealing with tough emotions in a healthy way.