I am currently working on SEO of a website. Two things that are bothering me on my test results from https://seositecheckup.com/seo-audit/www.qurantouch.com
It says my website is not using a custom 404 error page. Though I do have a custom 404 page. This is a sample 404 page. https://www.qurantouch.com/xzczxc/zxcxzczxc/zxczxczxc/zxczc
My site fails the Server Side Caching test. I have seen their suggestions are for PHP and wordpress websites. My site is built with angular7 and is hosted in an Nginx server. I need to a direction to enable server-side caching for my website.