What should I do now

Question

I know complete python(no django or flask or any lib just python till oops)
I have 3 years left in which I can learn anything so what should I learn Android development or web development or understand data structure or anything else

Answer 1

Depends on your intention. From your profile you are a python user thus learning Django framework is a good idea. Plus you know frontend, you need a database too (check SQL here)
So now you have:
Frontend : html css js
Backend: Django + database

Speaking of Android, you don't look to have experience in java or kotlin, for an android app you need a solid understanding of Java SE - Android SDK - XML - sqlite/firebase.

Another option is data science, now everywhere you choose to go, you need to understand data structures.