ReadEra is free to download and use on mobile. Using it on PC via an emulator is also free, though emulators may show ads in their interface.
If you prefer not to use an Android emulator, consider downloading these natively programmed desktop alternatives: Download ReadEra for PC -Windows 11 10 8 7 Mac-
No, because S Mode only allows Store apps. You would need to switch out of S Mode (free) to install BlueStacks and then ReadEra. ReadEra is free to download and use on mobile