What a young Nigerian can invest in to yield at least 18% ROI in Nigeria?

Kevin Ejerebe says:

Since February 2021 crytocurrency trading by customers operating accounts in banks have been put to a halt causing a lot of losses to crytocurrency traders and crytocurrency exchanges and the authorities have been saying they come up with ways to resolve this.
Four months gone and nothing.
The reasons the CBN and SEC gave were these- concerned about the crytocurrency trades which may lead to crytocurrency traders and investors lossing their funds and also terrorism being sponsored through crytocurrency but in the time past SEC have never shown concern about people lossing money in the stock market let’s take for instance the early to late 2000 a lot of people invested money in banks such as oceanic bank,intercontinental bank,platinum just to name a few and these banks folded up and disappeared with investors funds no refunds no explaination given.So why now the concern about investors lossing money?.
The CBN and SEC should something really quick because a lot of people have funds just lying idle in exchanges which they need to do other things like setting up businesses,further education,pay bills…
Like me I hold an account on luno exchange which doesn’t have a peer to peer facility put in place and I don’t like the aspect of transferring to another exchange because of these reasons the fee and guarantee of being paid or seeing your money transfered to your bank by the peer doing business with me.