How to Track E-mail read receipts using google analytics-4 , via image pixel tracking technique?

Question

I want to track the read receipts of the emails . using google analytics-4 , appscript and gsheets .

till now i have implemented

1. image pixel tracking technique but the email app (in my case gmail) does not allow the script to load , that is embedded in the html template of the email .
2. Also implemented using a website hosted on google sites , but that is also not working.