Here is how you can increase the number of the Bots in CS2.

10 Bots on Each Team

1. Open Console (If you haven't enabled Console, go to Settings > Game > Enable Developer Console to Yes)

2. Type "bot_quota 20" and press Enter.

More than 10 Bots

Valve removed the option to do this in the recent update and we will update the post if we find any possible way in the future.