Many modern "cracked" .rar files do not contain the game at all. Instead, they contain a script that, once extracted, runs a silent cryptocurrency miner. You will be playing a laggy version of San Andreas while your GPU secretly mines Monero for a stranger.
However, the internet has changed. The risks of downloading a random .rar file today—ransomware, identity theft, legal trouble—far outweigh the $14.99 price tag of the legitimate version.
A: No. Android requires .apk files. However, you can extract the .rar on a PC, then move the data folder to your Android obb directory for certain emulators (this is complex and still piracy).