Guys urgent !!!

I have asked for project release from my manager. I am working in FS unit currently. And my current tech stack is outdated and role is BE dev even though it's a support project. I only have to develop requirements then when uat phase start, support uat and client interaction.

So now which technology should I switch to so that I don't regret it later and something that helps in my career? Accordingly I will have to tell it to the manager and prepare myself for the project interviews.

I am thinking of asking for data engineer roles. Am I making a mistake?? Or should I go for java spring boot?

Please help share your opinions.