Mr @JayJuanGee dropped a tool
here which may or may not be that efficient enough to calculate based on the 200 - Week moving average on when to buy and also when to sell.
Lastly, knowing that Bitcoin investment is usually for a longer term and patience is needed even when the market falls in bearishness, this is understanding how volatile Bitcoin can be.
Whatever that is shared in this place by anyone is mainly for educational purposes and references. It shouldn't be relied on or be taken as a financial advice. When to buy or sell your Bitcoin is strictly your call and yours alone. It is always advisable to DYOR before making any investment decision. This is very important so that if your investment goes either ways you will know it was your call and not have to blame someone else.