If you look at the validation status of the domain, you’ll see the verification CNAME DNS records have not been set up. So to answer the question “how long does it take”, the answer is: for as long as it takes you to set up the verification records, plus a few more hours at most for DNS caching.
But even if you just look at the certificate list, you’ll see that you requested an SSL certificate for 42web.io, not for bannerman.42web.io. Because you don’t control the entire 42web.io domain, you can’t setup the validation records for it.
Please try requesting an SSL certificate for the domain you actually want to get SSL for. So that’s bannerman.42web.io, not 42web.io itself.