https problems with the plugin

Hi, I’m doing to do a new website, I’ve installed the One Page Express Theme and then it need the plugin One Page Express Companion, when I activate the plugin there’s some issue for the https protocol and I have not a full https response from the website. Then were I have to change the urls from http to https? because some images under an activated section is connected in http and not in https. Then will be different when I have completed the website and used other images into that section. https://sam-aps.ml/wp-content/plugins/one-page-express-companion/theme-data/one-page-express/sections/images/project1.jpg

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