generally, yes. you should make backups of your wallet before funding them in general in case of situations like this. wallets are generally recoverable, but the type of wallet and version you have will affect the recovery process. the easiest types of wallets to recover are hierarchical deterministic wallets, as they provide a recovery seed (string of words) which can be used to recover all addresses in the wallet. electrum and trezor are couple examples.
nothing is guaranteed. there could be bugs/exploits which have not been found yet. this is why HD wallets are so great..... if anything ever happens, you have your recovery seed.
as OmegaStarScream said, trezor or ledger are highly reputable hardware wallets. regarding whether they are safe....... to some extent, you are trusting that the hardware/firmware is not compromised and has not been tampered with. if you are not auditing it yourself, there is always a small chance of compromise. but these are very reputable companies. i would advise only buying directly from the manufacturer. don't mess with third parties who might send you a wallet that has been tampered with.