Issue using the cloze type

Cloze deletion can only be used in fields which use the ‘cloze:’ filter. This is typically the first field. - I need help I can’t use the cloze type on my cards.

As the message says, you should have {{cloze:Back Extra}} in the template for clozes in Back Extra to work. Just put the clozes in the Text field instead if you don’t have any reason to use Back Extra this way.