Coldwallet questions

I have a Ledger and it's nice and easy to use but I keep hearing scary things about it. I also got a Trezor a while back - just regular Trezor, does not say X or II or anything, but I read a thread that it was hard to transfer to another device from Trezor. Then I keep hearing things about firmware and connecting to a device without internet.

Sorry if this is a dumb question, but how can you transfer crypto to your wallet without the internet? I want the safest wallet but I am not a tech person and don't know what firmware is or any of that, I just want to plug something in and make it work. I heard Coldwallet is good. Do you guys concur?