There are many solutions available for online giving that work with WordPress. It is possible to create a button that links to a payment form hosted by your giving solution provider. It is also possible to embed a form for collecting tithes and offerings directly on your website. Some solutions have options for setting up recurring giving.

Below is an example of one giving solution. Please see How can we handle giving? for more information.

Giving Form
Screenshot of giving form from Tithe.ly
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