You're able to add a custom thank you message for your donors to see on the donation success screen.
To add the post donation text, following the steps below:
Step 1: Under Campaigns, select the Settings of the campaign you wish to edit.
Step 2: Under Sites & Forms, select your donation form.
Step 3: Select Post Donation Screen from the left navigation and enter the success screen message Save.
You can also add a redirect URL to send the donor to another web page after they close the form.