Optimize Shopify Website Speed

I need to optimize my website Shopify speed. There is some speed issues that need to be fixed and optimized for example the GIF image size is too big and needs to be fixed and optimized to make the website run faster.

Also, when you flick checkout the page takes too long to load. I need to fix this issue also.

Here is the speed test from Google with the issues:
https://pagespeed.web.dev/report?url=https%3A%2F%2Fgainbliss.com%2F