Extension menu

Dear T3 community,
I am new in the T3 universe and about to create a project. I installed Typo3 version 11 via Docker and DDEV on my Mac and everything just went fine.

There is just one thing. There is no possibility to work on the extension menu. It shows me:

The system is set to composer mode. Please notice that it is this list is for informational purpose only. To modify which extensions are part of the system, use Composer. To set extensions up, use the TYPO3 cli (extension:setup)

So, I am unable to upload the extension I want to use.

Is there an article with information regarding this problem or a different way to handle this?

Or could you please be so kind and help me with some kind of instruction guideline?

I am looking forward to a reply.

BG Daniel

Hi Daniel,
welcome to TYPO3. Please use composer for installing extensions.
https://docs.typo3.org/m/typo3/guide-installation/10.4/en-us/ExtensionInstallation/Index.html

BG Robert