I would just grind leetcode. I am not sure how much help a project would be with regards to landing a job. I guess it would be something interesting to talk about in an interview, but would only be interesting if the project was actually interesting. So if you could find something that allowed you to stretch your brain go for it. I would check out
WSO - they have a lot of forums that you may find something on. But again, grinding DSAs for
C++ would probably get you through the interviews.