Difficult to comment without URLs, there's too many potential causes
Unfortunately "[being] a web designer since 2016" is generally not helpful for SEO
But certainly setting up Google Search Console, submitting a sitemap, and 'fetching' your homepage on day 1 is good practice, especially for a brand new website
Unfortunately "[being] a web designer since 2016" is generally not helpful for SEO
But certainly setting up Google Search Console, submitting a sitemap, and 'fetching' your homepage on day 1 is good practice, especially for a brand new website