How to generate a 24 words seed with a passphrase ? I just tested to select "add words" and put a password when I import a seed but it's impossible to click on next.
It should work. You probably did something wrong.
Use the command above to generate a 24 word seed phrase. Then, Create a new wallet. Select "Standard wallet" and then "I already have a seed". Click on "options" and check "Extend this seed with custom words". Enter your 24 word seed phrase, then your passphrase and click "Next".