thunderbird is not saving messages from my email server

[linux_trojan]

I use Outlook for email. I have it synced with Thunderbird. However, I want to keep all my emails. If I delete a file on Outlook, it gets deleted in Thunderbird. I thought only Pop3 did that? I dont think I selected Pop3? Nevertheless now I cant find where those settings are in Thunderbird.

[gittiest personITW]

Look in TB,
Edit / Account Settings / Server Settings

[linux_trojan]

I am in Server Settings right now. First thing I see is

Server Type: IMAP Mail Server

I dont see option for Pop3, no options at all. What am I looking for?

[linux_trojan]

I just tried Evolution - same thing. Is it a problem with Outlook? I disabled Pop3 in Outlook.

Maybe I can automatically send all emails from Outlook to Gmail and use IMAP there?

I have had this email since 1997. I cant give it up.

[linux_trojan]

I found the solution.

https://support.mozilla.org/en-US/kb/changing-imap-pop