To request a captcha to fulfil, you must use
m.verify, this will DM you with a captcha that Mila has just generated.
Failing a captcha will result in a message providing you with the number of attempts you have remaining and a retry. You can continue to attempt the captcha until you run out of attempts.
Completely failing a captcha will result in a prompt telling you to generate a new captcha in the appropriate waiting channel, this cycle will repeat until you finally get a correct answer.
When you give a correct answer to a captcha, you are given the configured Members role and access to the server. You are now free to enjoy the services of the server as you normally would, knowing that the chances of a successful raid are slim.
If a user is really struggling with a captcha, Moderators can use
m.pass <@user> to give the user access to the server, this is handy in the event that someone is having serious trouble completing a captcha or is already trusted by staff.