Interview with Meta in 3 weeks. Haven't leetcode in 3 years. Am I cooked?

I got a sudden interview with Meta in 3 weeks which I wasn't expecting. I haven't leetcode in 3 years so I basically forgotten everything. On top of that, I haven't used Java or C++ in years.

How cooked am I? What is the best way to review and cram within this timespan? 1 hour a day? 2 hours a day? I don't have high hopes that I'll pass, but I do want to try my best in case performance impacts the cooldown period for interviews.