I'm going to be buying some cryptocurrency for long term investments.

What are you using for secure bitcoin storage?

I'm not going to be selling it/using it for purchases, it's a buy and hold strategy, so easy access to it isn't top priority.

I'll be probably buying some Ethereum, but will likely be buying others as well.

Currently looking at BitKey OS, or Tails on a USB stick with wallet. Ledger Nano S will probably end up being my choice but they're not in stock right now.

A paper wallet works extremely well.

It is what I use to back up my brain wallet.

Paper wallets have their place, but im looking at ledger nano s and opendime for hardware wallets

Please :
Tell me more, explain as if to an old person.
Can one securely hold BTC, or LTC in hand, on let us say a thum drive ?
 Are there transfer fees, for converting such private storage ONTO  a liquid exchange facility ?