https://devdocs.magento.com/guides/v2.4/frontend-dev-guide/layouts/layout-overview.html
https://bssthemes.com/blog/magento-theme-layout/
Exercise:
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In product detail,
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change price of product to “red” color
In product detail,
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add category information before add to cart button
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Add form customer login
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to all magento frontend page, process to login.