Non-Muslim Women
32 – Rule: It is not a problem to look at those parts of the body that are not normally covered by non-Mahram women who are not Muslims (whether they be from the Ahl al-Kitab, or Kuffar), with the condition that it is not done with the intention of lust. However, according to Ihtiyat Wajib, a man is not allowed to look at those parts of the body that are normally covered.
https://www.al-islam.org/code-ethics-muslim-men-and-women-sayyid-masud-masumi/rules-related-looking-others#e-non-muslim-women
I would like to ask about regard gym app which helps for you to work out at home or outside, the app itself has males and females videos show you how to workout. The female show video how to workout is it permissible to watch video
It's ok but not with lustful intention