Pre-requisite: You need a paid Framer account to access Custom Code.
Installation Guide
Here's how you install Mida script on your Framer site:
Log in to Framer account.
Select the project and click on the Framer Icon > Site Settings > Open Settings.
In the "Site Settings > General > Custom Code" section, paste the Mida tracking code, then Save and Publish the changes.
Congratulations, you have installed the Mida tracking code!
Tutorial
Here is a YouTube Tutorial on how to run A/B test on Framer: