The general behavior of your registration codes is set in

This page has two groups.

Registration Code Settings

• Mandatory registration code: if checked, users can’t register if they don’t use a code. A mandatory code is asked in every registration form of the plugin, whatever the options of the next group.
• Code Length: the length of the codes the plugin generates automatically. The default is 8. The maximum is 64.
• Code Pattern: this text prefixes the automatically generated codes. You can also write [code] inside the text: it is replaced by random characters. Without [code], the random characters are added at the end of your text. Leave the field empty to get codes made only of random characters.

The length and the pattern are used when you leave the code empty in the code editing screen, and when the plugin generates the codes your members share (see Let Members Offer a Membership). Codes you type yourself are kept as written.

Registration Code Field

Select where the registration code field should be displayed. The field is optional unless you made the code mandatory.

• Display a Registration Code field in the WordPress registration form
• Display a Registration Code field in the WooCommerce registration form
• Display a Registration Code field in the WooCommerce checkout form

The two WooCommerce options only appear when WooCommerce is active. The article Where Users Enter Their Code shows what your users see and what happens when they submit a code.

If you want a registration form that is not WordPress’ or WooCommerce’s, build one on the Registration Form page. See Build a Registration Form.