Google Tag Manager allows you to set up and manage GA4 events all in one place. To send event data from Google Tag Manager to GA4, you need two tags that work together:

• Google Analytics: GA4 Configuration
  The GA4 Configuration tag ensures data flow from your website to Google Analytics. 
  Create one configuration tag on every page where you want to collect analytics data.
• Google Analytics: GA4 Event
  The GA4 Event tag lets you set up events on your website without writing code. The event data shows up in your GA4 reports.
  • Create as many event tags as you need to measure your recommended or custom events.

  

Reference: 

https://support.google.com/tagmanager/answer/9442095?hl=en