Can I create two different graphql query for two different folders separately in my Gatsby project

Question

I'm a newbie programmer and Recently I want to add a blog page to my website. I already have a projects page using Graphql and .md files, now my problem is, every time I try to create a blog post with .md, it appears also in my projects page, could you please advice me with some of your kind experience on solving this issue and do I have to create a separate query? even I don't know how?

this is my current query.

export const query = graphql`
  query ProjectsPage {
    allMarkdownRemark(sort: { fields: frontmatter___date, order: DESC }) {
      nodes {
        frontmatter {
          slug
          stack
          title
          thumb {
            childImageSharp {
              gatsbyImageData(placeholder: BLURRED, layout: FULL_WIDTH)
            }
          }
        }
        id
      }
    }
  }