Exist any sort of "physical wallet" for BTC? How is safe and how cost?
Physical wallets can be either Paper wallets (which basically cost nothing but a paper where you print the private key and the public key) and there is also Hardware wallets like the above user suggested , but I personally would choose Case wallet if I had to go for a Hardware wallet , see here :
https://choosecase.com/ It's little bit expensive but if you had huge amounts then I think it really worth it .