OP, if you plan to generate password randomly rather than creating your own password that you can remember, i strongly advice you to use offline password manager such as KeePassXC.
Don't use a password generator website. Thousands of Bitcoins have been stolen this way. Even if you use if offline, it is HIGHLY LIKELY to give you intentionally or unintentionally predictable output.
If the random password generator is offline, there is nothing bad to use it, but I consider it stressful than to randomly input different characters on my keyboard, but that does not mean it is not safe, nothing connected it online, but use the recommended ones. If connected online, then it is not advisable because we do not know what is running underground to steal the password online in the process of creating it.
Read @pooya87 reply. Even if it's offline, we don't know the generated password is truly random or rigged where it's search space is far smaller.