In short, you should use an open source, non custodial wallets. If you can not buy a hardware wallet, you can use free wallet software (should be open source, non custodial wallet) and set up your cold wallet or multisig wallet. Like you can do it with Electrum wallet.
- [GUIDE] How to Safely Download and Verify Electrum
- Cold storage / multisig wallets
- [LIST] Open source hardware wallets
Reminder: do not keep your money in online accounts
Everything the OP needs is quoted here. Thank you tranthidung for the work searching it and summarizing it here.
IMO, Electrum is the wallet to start with, while you think about purchasing a hardware wallet, but there are other good alternatives too if it was not enough.