Adds a new component called HeaderMain that renders a navigation bar with links to different sections of the website.

The component uses a list of navigation items defined in the `navList` array. Each item in the list contains a title and a link.

The `LinkComponent` component is used to render each navigation link. It takes the title and link as props and renders an anchor tag with the appropriate href attribute.

The `HeaderMain` component renders the navigation links by mapping over the `navList` array and rendering a `LinkComponent` for each item.

This commit adds a new component that will be used to display the navigation bar on the website.