Hello Dawn,
Thanks for asking. 
- If you just want to remove Filter By Category text, please add following CSS under X > Theme Options > CSS:
.x-index-filter-label {
display: none;
}
2.To remove the Filter By Category tab, please use following CSS under X > Theme Options > CSS:
.option-set .x-index-filters {
display: none;
}
3.To change the order, it will require some custom development work which falls outside the scope of support we can offer. However, I can tell you the file name and the file path that you can take a look and make the changes per your requirement. Under /wp-content/themes/x/framework/views/ethos/ please open _index.php and make the necessary changes.
Having said that, I suggest you to install and setup child theme before making any changes. You can use following resources to download and setup child theme.
Download Child theme from following source: https://theme.co/apex/child-themes
Please take a look at following article to setup child theme:
https://theme.co/apex/forum/t/setup-how-to-setup-child-themes/57
Thanks.