You need Jetpack - Portfolio module enabled to use this section. Projects will appear here once you activate the plugin. You can also disable this message from Customizer > Settings > Extensions > Disable helpers/placeholders.
What goes into a blog post? Helpful, industry-specific content that: 1) gives readers a useful takeaway, and 2) shows you’re an industry expert. Use your company’s blog posts to opine on current industry topics, humanize your company, and show how your products and services can help people.