About to join TCS(digital), any advice for me

Learn as much as you can in 2-3 years and switch. On a lighter note, its just a first step in a very long journey. Enjoy your days while you are at it. All the best!

Apply in startups, you will get a much much much higher rate of learning and progress.

Do not take up a project which has an outdated tech stack

Keep grinding on leetcode, since you are digital you will get multiple calls ask them about the techstacks properly and everything.

Try to get into a developing project. They will put you in a random project regardless of what you got trained in. The first project can decide your career path, if you are in a good developing project. Then you can upskill in that field and switch easily, but if you are in support it will be harder to switch