Everything related to autorouting or autorouter (automatically routing the layout with some algorithm) has been discussed many, many times over.
- Where to discuss autorouter/placer?
- Tensorflow based autorouter
- Autoroute? Is it coming? (Mod edit, short answer is not in the foreseeable future so nothing to see here. ;) ) (includes comments by several KiCad developers)
- V5 and the autoroute icon
- Why do people choose to NOT use the auto-router?
- Newbie question about autorouting
Do a forum search to find more.
KiCad once had some kind of an integrated autorouter, not very good, and it has been removed long time ago.
KiCad (pcbnew, the layout editor) can export a Specctra DSN file which can be used by some external autorouters. The result can be imported back as Specctra session.
There exists one open source autorouter, freerouting, but its history (legal status) has been somewhat controversial, it’s a java program and there’s no one authoritative source found because it’s not really developed anymore, but there are a few “forks” available. Do a forum search to find out more information about it.
A related problem is autoplacing. As some people will tell you, placing the components is even more time consuming than routing, and it’s critical for successful routing, too. It’s more difficult to do it reliably in some automated way than routing. As far as I know there’s no solution for that unless this project can help. Most of the realistic solutions just try to help with the initial placement so that it’s a bit easier to continue manually, for example by placing the footprints roughly in the same way than the symbols are placed in the schematic. See for example Automatic Optimized Parts placement on PCB and the plugin by jenschr and ian-ross.