It takes longer when you first start, but you soon get used to what portion sizes of your regular foods look like, so less need to weigh.
For example 1/3 cup of oats, is that estimated? I got used to weighing out 40g of oats. Then after a while I didn't need to weight because I knew what 40g looked like.
Likewise, tablespoons of anything is massively inaccurate. If start off with weighing the 2tbsp yoghurt (By keeping bowl on scales after adding the oats). After a few goes you'll know how many grams your 2tbsp usually are.
Likewise your fruit. Keep your bowl on scales. Weight 40g if oats. Weigh 30g of yoghurt (or whatever your amounts are). Then add the usual amount of cherries you add (a handful?) and see how many grams this is.
After a while you'll be able to know, or at least estimate, what how many calories are in your breakfast as you make it. Then you can start thinking things like- if I had milk instead of yoghurt, how will that affect calories? What if I just added cinamon and no fruit? How about if I used a banana?
The idea of calorie counting is essentially self-education. So you learn how many calories things have in them. As with anything you learn, the more you do it the easier it becomes yo do.