I hope you are well today and thank you for your question.
In WordPress posts are created to display dynamic content and pages are used to display static content but if you want to use pages instead of posts then to achieve this, you have to develop custom code in the child theme of Gillion theme.
Developing custom code for custom functionality is beyond the scope of support that we provide here.
If you are not a developer then you can consider hiring a developer to develop it for you. You can hire a developer from any freelance site. Shufflehound recommends the developer https://www.upwork.com/freelancers/~011652ffec8865c6d5