Will I be able to integrate Google Tag Manager into my Partnershop?

Yes. You can integrate Google Tag Manager into your partner shop.

To do this, go to the backend section Marketing > Online Marketing. [1]

Under the Google Tag Manager module [2], please enter the details you have – your Google Tag Manager ID –
into the input field. [3]
Clicking the ‘Go!’ button [4] will save the ID permanently.

You must have a valid Google account to do this.