How to prepare for the next jump?

Java Full stack dev with almost 7 YOE

Have exposure till Java 17 features, know JavaScript and React JS, mySQL for DB, spring boot experience. Having a little bit of experience with type script. But I have work level experience in everything. How to prepare myself for a solid interview? Currently I'm earning 15.5 LPA and I'm planning to jump to a product company with a hike of around 60-70%

Planning to make a jump in the next 6 months. Took the roadmaps from roadmap.sh and started to follow it accordingly.

Solved some easy SQL questions in leetcode. Now into Java, brushing my basics.

How to practice streams and other problems?

Brain rot is real. Even if I'm not able to solve one or more questions, I feel like giving up. How to overcome it?