Frontend-react.js, Backend-laravel, fixing 3 issues.

I have a site where the frontend is React.js and backend is Laravel. I want to fix 3 issues. 1-When files are uploaded the system does use a random filename. Filename should be the same name as the local filename. If the file exists it should ask if it should overwrite the file 2-When setting the Screen size in the admin->settings menu to another size like 1080x 1920 (screen is rotated) the screen div in the "Playlist" menu is still in the old scale format 3-In the menu Playlist and then selecting a playlist the user may add or remove media "Add or Remove medias" at the moment it is only possible to add a media only once. It should be possible to add an media item multiple times to a playlist. If you can do it within 3 hours, please bid for this job. My budget is $50. If you are an expert, these are no problems. Thank you for your time.