Provided that you have at least an NVIDIA GeForce 510 graphics card you can play the game. You will need at least 500 MB of free disk space to install 21+. 21+ system requirements state that you will need at least 512 MB of RAM. An Intel Pentium 4 2.00GHz CPU is required at a minimum to run 21+.
21 will run on PC system with 10, 7 and upwards. Additionally it has a Linux version.