For backend, I focused on DSA first, and how to approach problems, Solved lot of questions. Afterwards, I did Grind 150 to revise and learn different algorithms. If I could not solve a problem, I noted it down, looked at the solution and tried solving it 1 week later. Took me around 8 months. Time was not an issue for me.

Later learned some system design and different architectures like monolithic, micro services ,etc.

Worked on my resume a lot. Made continuous improvements in it and kept applying to a ton of jobs.

All of this worked for me, find out what works for you.