After the heavy downfall of cryptocurrencies, I am planning to make use of this cheaper prices. Where I can invest to get at least 5 times returns in next 2 to 3 years.
That's a million dollars question everybody is asking, and frankly, no one can give you the right answer.
If you ask me, I can say only one thing that makes sense to me:
keep your BTC!
The only long term investment where you are certain to be winning is BTC. Period.