Hi Nicu,

Actually, Odoo has not made it very easy to do so :)
You will need to do the following steps:
1. Create a new Website Live Chat Channel under Live Chat > Channels
2. Create a new chatbot (with possible questions and answers) under Live Chat > Configuration > Chatbots
3. Now go back to your previously created channel and on the channel under the "Channel Rules" tab create a rule and connect the chatbot there.
4. Now, finally, go to Website > Configuration > Settings and make sure the option "Livechat" is activated and that you've connected the live chat (channel) here too.
5. If you now go to the website you will see the bot available.

I hope this helps :-)

Regards,
Yenthe