What to do Know?

Hello, every one a little background about me. I am currently a sem 5 student at one of the tier 2 NIT in CSE. As companies will about to visit for internships in starting of AUG. Currently i am having 300+ problems on LC and 300+ on CF.
i have 2 project in MERN. As in my 5th sem i have ML. So thinking of to learn ML. What is the best approach or should i do Data science. Please help