In most part of Africa hardware wallets are not only difficult but expensive to get apart form using custodian wallets like trust wallet and metamask is there an alternative software that can help hodl Bitcoin in a flash drive. or otherwise
You can store your coins in any way you want, it is just that a hardware wallet is a very safe way to do it, however if the supply of those hardware wallets is on the low side where you live or their cost is prohibitive for you then you can choose several other alternatives.
Since you are posting in this forum then this means that you have access to electricity, the internet and a computer or a smartphone, meaning that you already have all what you need in order to store bitcoin securely, now you can store a backup on a flash drive if you want, just remember that those flash drives have the tendency to die down after a few years, so do not use them as your main way to store your coins.