If you created your Google Analytics property before October 14, 2020, you are likely using Universal Analytics and should make the switch before July 1, 2023. Analytics accounts created after this date may have also had a GA4 property created.
To check to see if your Google Analytics is set up for GA4, check your account’s properties list for a GA4 property. As seen in the image below, if your website has a GA4 property, check for a green “connected” status to ensure that it is installed correctly and properly tracking.