You can set various donation amounts in admin panel which will display on the donation form.
To do that you need to go to your WordPress admin panel and find the menu WP Stripe Donation. Under that menu, find the sub-menu General Settings.
Then you need to find the option Form Amounts in this page.
In this field you need to apply comma separated numeric number like 10,50,100 etc.
Save that settings page and you will see multiple donation amount option on your donation form.
