You can use UkuuPeople and Gravity Forms to create donation pages for your nonprofit. Below is a sample donation form which is linked to UkuuPeople. Give it a try to see how it works. Fill out the form and submit it and then log in (using the login widget) to see the info you added on the UkuuPeople dashboard.
*Payment processor is in test mode so no live transactions will be completed.
See the full how-to article for setting up your own Donation Page here.