If you're trying to test your website tab navigation and the link (anchor tag) is not being focused, it might be the case it's missing href attribute:
<a>I'm not focusable</a>
<a href="/">I'm focusable</a>
In fact, they also have visually different style:
![Anchor tag with and without href](/_vercel/image?url=https%3A%2F%2Fcdn.sanity.io%2Fimages%2Fgc3hakk3%2Fproduction%2F7ed825ba95fa41beb7cb5695727732114d8ae193-540x174.png%3Fw%3D540%26h%3D174%26auto%3Dformat&w=640&q=100)
But this can be a bit tricky when you're using global styles to normalize all anchor styles, no matter its state.