I installed LineageOS on my Samsung device, and there doesn’t seem to be a radio app. I have access to an identical device which is running the stock OS. I extracted the radio app on the other device (with App Manager) but cannot install it (unavailable shared library com.samsung.device). (Galaxy A21s, Exynos.) How can I listen to the radio on this device?
Do Samsung phones even have FM antennas? As far as I know they have to be a minimum length and old school feature phones had a hacky workaround where you had to plug in earbuds to listen to the radio because it was using the earbud cable as an antenna. Modern Samsung phones don’t even have headphone jacks so I can’t imagine they support FM at all. Probably your best bet is to use an internet radio service that has access to the stations you like.
My phone does have a headphone jack, and I could listen to the radio on the stock ROM using the workaround you mentioned.