Then according to your body type and endurance keep incresing the time and pattern of exercise.
For Cardio at your age 25-30 mins a day is more than enough
If you’re trying to improve your fitness, then a little something each day is optimal. Shoot for 20-40 minutes 5-6 days a week; but also don’t be too hard on yourself if you miss it sometimes. You’re at a very busy age, and time management can also be tricky!
Take your bicycle when possible and do a yoga stretch, and maybe go for a nature walk- it adds up easily when you look for opportunities. You can totally do this; I’m so happy for you to be considering your health at such a young age. I’d love to fast-foward 20 years and see how you’ve made out. You sound very interesting!