Jquery added element removing automatically

I haven’t found any selector for the Rent button. Also the age checkbox need to create via code. How can i do that all process via wix code. There have no proper documentation. Can you give me an example code so i can get idea what i need to do. Also i have not found any reason why Wix remove jquery code. You can check this screenshot https://drive.google.com/file/d/1Hrhx-NGC61VY6fIRmlwKOzArO4VReKyH/view You can see on loading the text showing but after finish loading it’s removed automatically. I added this text via jquery insertAfter method.