Check the Shopify apps you have installed and remove the apps you no longer need. If applicable, be sure to remove the code from the theme file. In many cases, there's a lot more to do than just remove the app from Shopify.
Talk to your theme or app developer to find out how Clipping Path Service to improve load times. Shopify is also investing in this measurement from an app perspective.
Consider migrating to the Shopify Online Store 2.0 theme approved by Shopify to meet your speed expectations.
Consider migrating to an app that is fully compatible with the features of Online Store 2.0. Make sure your app doesn't leave any code after you delete it.
Remove unused tracking codes from apps like HotJar and LuckyOrange.
Delete the Instagram or Twitter feed and replace it with an image or text that looks like the feed, but leave it on your site.