Will your website still be hacked despite these measures?

there's always the by left and by right. your website must first be developed in a secured manner, you can ask ur developers to comply to OWASP coding standards.

SSL and cloudflare do not protect from web-defacement

SSL simply provide your user a more secure environment with a signed cert

Cloudflare wise i believe will notify you when your website is down or having issue but not on changes and defacement

For Defacement Detection notification there are several open source tool out there that will pick up changes and notify the owner if any changes/defacement are picked up

there is no 100% defacement prevention technique out there in the market. just ways and method to reduce the probability of being defaced.

there are also tools out in the market that will show a vulnerability stripped page when a defacement has occur. this will buy you sometime to do the necessary recovery and patching when ensuring that the defaced page is not shown to the public

Hmm. Actually the key question is whether u r even aware when your website is being hacked. Because many sites have been hacked for months or even years before someone realised. So one area is to do log reviews and if budget allows, get SIEM.

The quick answer is yes if your website is developed in a insecure manner. not easy task even for many top sites in the world. implement more detective systems to help monitor your website.

Cheers!

If I have installed SSL cert for my website and protected by Cloudflare, will my website still be hacked?

minimally install SSL