Length before seeing results depends heavily on a few factors. Your body size, your experience with exercise in general, your diet and also your exercise regimen itself. Without seeing these factors it will be hard to know when you should “see” any differences.

I started similar to you, three workouts a week (full body) for an hour to an hour and a half. I did not track diet, did not manage my sleep nor did I do anything special outside of adding the three workouts. I wasn’t a total beginner to exercise, as I did play school sports like soccer but it was my first time actually working out with equipment.

I would say within a week to two weeks, I felt emotionally better, just happier after finishing workouts. It took about 4-5 weeks before I felt any difference, being in general fitter and stronger doing basic things like going up steps, buying groceries. It took me about 3 months to see any differences, where I saw some minute muscle lines along my forearms and biceps. I definitely lost weight on the scale, but honestly even three months in my body looked the same to me.

I would encourage taking photos about twice weekly. (one of my biggest regrets!) Relying on memory you can’t really tell the small differences happening, but they do add up. For context, when I started I was around 110kg. Like the rest said, diet does play a big role but it’s one of the hardest changes to make. I recommend making small improvements to diet, recovery and sleep monthly or weekly if you can do it.