KiCad has no build in autorouter. (There was a bad one in the past but that got scraped because it was bad and no longer compatible with the program)
The only option i know off is to use freerouter. You can generally search the forum for this term. I think this might be a start Announcing kicad_freerouting-plugin (I have not followed the state of it)
Oh and for a bit of fun: https://contextualelectronics.com/product/never-trust-the-autorouter-t-shirt/ (Merch that supports KiCad development sold by the guy running this forum)