Sort:  

i guess you're new to cryptocurrency.

get your coins off exchanges and into nano ledger s or trezor so the coins are offline, keep the ledger in a fireproof small box keep the seed words in fire proof small box some where else and keep copy too.

key logging software is used every hour by criminals stealing cryptocurrencies from coinbase etc when they are gone they are gone, get a crypto education or get recked

yes i am new and i have not enough idea about it that is why i asked you.please give me answer

Safe enough. As long as they don't get hacked or run off with the money.
Or you can manage it all on your own device and hope you don't get hacked.
If you intend on buying and holding then look into an offline wallet that you can backup your private keys yourself

Coin Marketplace

STEEM 0.15
TRX 0.16
JST 0.028
BTC 68787.29
ETH 2435.35
USDT 1.00
SBD 2.33