Set Category as navigation link

Under the ‘Recipes’ link on my navigation panel, are sub-pages under the name of ‘Breakfast’ ‘Lunch’ and ‘Dinner’. I’d like these sub-pages to link to the Categories of the same name. However, I am unable to change the name of the URL slug to link this correctly within the pages editor.

I’m new to wordpress so would appreciate simple explanations where possible! Thanks.

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