Computer Science vs Informatics Practices
Both use Python. One is about how computers work; the other is about working with data.
The difference
Computer Science (083) is programming-heavy: Python in depth, data structures, Boolean logic, computer networks and SQL. Informatics Practices (065) is lighter on programming and heavier on data handling with Pandas, data visualisation, SQL and societal impacts of IT.
Which to take
Take 083 if you want to program, aim for B.Tech CSE, BCA or B.Sc Computer Science, or simply enjoy logic. Take 065 if you want data skills without deep programming, or you are in Commerce or Humanities and want a practical, scoring fifth subject.
Rules to know
You cannot take both. CBSE does not require Mathematics with either, but many schools pair 083 with Maths in their blocks, and B.Tech CSE needs PCM regardless.
Guidance based on the CBSE scheme of studies and public exam bulletins. Confirm rules with your school and the official sources before deciding.