Your donation form automatically has a checkbox that gives donors the option to receive updates from your organization.
You're able to manage this checkbox.
Here's how you can find the checkbox settings:
Step 1: Under Campaigns, select the Settings of the campaign you wish to edit.
Step 2: Scroll down to Donation Form and select General Settings.
Step 3: Enable Subscriptions to display the subscription option on your donation form.
If the donors check the box, they've indicated that they'd like to receive your communications.
Step 4: You can also enable Subscribe By Default so that the option is automatically checked off and the donor has to uncheck the box if they do not want to receive your communications.