Check box based filtering of SharePoint list

I have a SharePoint list with one of the column as "Status" that holds values like "Not Started", "In Progress", "Completed" and few more. I already have a Search box (JavaScript code in CEWP) where we can filter list items based on text string entered. It works fine. However, since the list is getting larger day by day, the search functionality is getting slower. Around 80% of the items in the list are with "Completed" status. So, we want to have a functionality where we can include or exclude the Completed items from search as required. Sometimes, we still need to perform a search including "Completed" items as well.

=> My goal is to have a check box labeled "Completed". The function of check box would be: *When Checked - The SharePoint list will Include "Completed" items (Other items with Status "Not Started", "In Progress" etc should be there always)

*When Unchecked - SharePoint list will Exclude "Completed" Items but keep others

Also, the search box I already have should continue to work.

I tried to search for this, however, couldn't find it. I am not very good with JavaScript, however, if someone can help with code that can directly be implemented on CEWP, it will be great.

Thanks in advance.