Disable Video Upload For Real Estate Responsive Theme

I would like to disable video uploads by users on the Real Estate Responsive Theme.

I have tried the solution outline in the thread https://www.premiumpress.com/forums/topic/only-allow-images-for-file-uploads/ but it does not seem to work for me. Also, there is no php.ini file on my server that I can see.

It was also suggested I try modifying the tpl-add.php file in the child theme directory. However, I do not have the coding skills to do this.

Does anyone have a solution to this. Or alternatively a way to limit media file sizes (including videos) to about 1 Megabyte in size. The first solution is preferable.