Linux
To check the architecture in Linux, open up a Terminal and run uname -i in there.
If you see x86_64 in the text displayed by that command, you’re good to go! You can download Feren OS for your machine.
If you see i686 instead, Feren OS is likely not compatible with your machine - you can still attempt to download Feren OS, however it may fail to boot and instead tell you This kernel requires an x86-64 CPU, but only detected an i686 CPU.