Just always check nutrition info, some of these that are presented as healthy are really not that great. In general, cereals are pure carbs pretty much so should limit the quantity to what you need in carbs, but they can also have a lot of fiber and be fairly efficient in terms of satiety to calorie ratio, I recently switched back to a small bowl in the morning for breakfast.
Muesli is great but imho the ratio of satiety to calorie is way better with the cereals and a splash of milk, I get something that feels like a “meal” for like 250cal, would be much more for a bowl of muesli that doesn’t feel like I’m starving myself.
I use a nutty muesli to top quark yoghurt, that’s a great snack/dessert I get 25g protein from the quark and the muesli I just put 15/25g on top which already almost doubles the calories but does make the whole thing much nicer, it’s a daily staple for me.
Yes, I’m pretty far in the deep end of calorie control right now _’