Please know that I am not an expert but just happened to know the Glucose Goddess pointed out that oat milk is really liquid starch and this can convert to sugar in the body.
I have also had to work against fat growing around the middle.
Did you know a lot of people think a little fat is helpful? (Even if it makes calories look higher.)
I must say though that your one cup of latte certainly seems perfectly reasonable!
A bit of meat, fish, eggs or tofu with plenty (a lot) of green vegetable and a drop of olive oil seems to be the sort of meal that helps ward of snacking hunger while keeping middle-aged middles down.
Then some nuts, avocado, peanut butter not too sugary fruit for snacks. Or something like celery + cottage cheese or hummus. Basically Look for some protein, a little oil, and lots of fresh leaves and fruit like berries and maybe sharp apple.
Stay away from sugar, too much starch, and too much fat as in chips, toast and butter, lots of cheese. People say full fat live yogurt is best.
Artificial sugars are said to drive cravings.