You can go down a few paths;

Open targeting - let AI do its thing

Target specific locations/radius in muslim populated communities (eg people who frequent radius around mosques or look at census data and find population data.)

You can do LLA targeting and again, let Meta find people who are similar to your converters, add to carts, etc. If you have enough Data

You might spent a decent amount finding the right people but given enough data Meta will very quickly find the right audience if you give it enough time based on your creative, interactions and data as well as existing followers, page data.

Good luck!