To change the Intro images, you have to use your own images. These images must be in .svg format. We have used images from the following site: https://storyset.com/. You can get the images from there too.
Select your 3 images and rename them to inro_1.svg, intro_2.svg and intro_3.svg.
Go to the assets/images folder and paste and replace with the existing images.
Change Intro Background Colors
Go to the lib/configs/app_config.dart file and change the selected colors.