Depends what you want to pursue later in your higher studies:
1) If you want to be programmer:
Backend languages: C, C++
Scripting languages: Python, PHP
Web Design and Framework: Angular JS, Node JS, Django
Database: MySQL, MongoDB
Need to be good in formulating logics and algorithms to make your programs more effective.
2) If you want to pursue something in Data Science: Learn more about visualizaton tools such as Tableau. You need to have good knowledge on Statistics, how to play with number and data and to put that data in human understandable manner.
3) If you want to be graphic Designer, you need to be creative and have a good know of how to use Adobe photoshop.