I am not sure what you are wanting to delete. I infer (from Google Translate) that you want to delete the inbox, but I think that is incorrect. Please provide more information. Thank you.

Thank's. Thunderbird segregates received messages for 4 parts: "newslettery", "offers", "notifications" and "communities". It's a problem for me. I want to have only "received" and "spam".

Is this a Gmail account? if so, those are categories set within Gmail, not done by Thunderbird. Highlight the gmail account in left side of main pane, rightclick and select 'subscribe' and I think you can untick any folders you do not want. Those other folders are duplicates of the messages in your inbox. Please let me know if this works.

It's not gmail. It's wp.pl

Okay, but it's the same type of issue. Thunderbird is not separating the mail into those categories; it is being done by your email provider.

Ok. Very thank you!!!