I have been playing around with Ian Coleman's BIP39 generator tool: https://iancoleman.io/bip39/.  What really makes this one stand out is that you can click "Show entropy details", and then it allows you to put in dice rolls, coin flips, etc to see it create seed phrases in real-time.  It also supports virtually all technical aspects of key generation to get a good sense of the many different options that are available.  It's kind of crazy how many types of addresses there are such as BIP44, BIP84 that wallets just choose for you (and creates all kinds of cross-compatibility issues).  You can also get things like the XPUB address to support multi-sig and all kinds of fun stuff. 

For people who do want to use this, you should use the github version and download the standalone page to use offline: https://github.com/iancoleman/bip39, as well as have a good understanding of the main concepts.  Otherwise using a Trezor like krogoth recommends is probably better if you just want a safe and user-friendly option.