I think investing in cryptocurrency is safe as it is in your trusted cryptocurrency wallet or exchanger. I think I could recommend you Coinbases for your investment using the coinbase mobile application you could easily buy this cryptocurrency for your investment and in my experience, I don't get any problem when it comes to security in coinbase.

Having a long term investment in an exchanger is not recommended because a lot of exchangers could stop their operation because they are bankrupt and you are going to lose your investment their if you are not aware. But for sure you could easily try a popular exchanger like Binance for your investment the support is great so I think it's safe as long as you have a different layer of security in your account.