Right to Left deployment


I am trying to make a test implementation of CoursePress Pro in Arabic (over a WP arabic deployment) and would appreciate your help with the following:

1) Forcing interface elements to become Right to Left
2) Directing me to how I can change the CoursePress Pro default labels to Arabic

I had seen a post from 2015 of a developer who had issues with his arabic/hebrew deployment and support staff Vinod advised him to use the following plugin to solve point (1) above, but I could not understand where to insert this code. The following code was provided by Vinod as means to fix this issue.

add_action('admin_head', 'my_custom_admin_css');

function my_custom_admin_css() {
echo '<style>
html[dir="rtl"] .chosen-container .chosen-drop {
right: -9999px;
left: auto;
html[dir="rtl"] .chosen-container.chosen-with-drop .chosen-drop{
right: 0;
html[dir="rtl"] .unit-details .unit-control-buttons .button.button-preview,
html[dir="rtl"] .unit-control-buttons .button-units.save-unit-button {
width: auto !important;
display: block !important;
float: right;
margin-right: 10px;
html[dir="rtl"] body.wp-admin #unit-pages .module-title span.h3-label-right {
position: relative;
html[dir="rtl"] body.wp-admin #unit-pages .module-title span.h3-label-left {
display: none;
Thank you