How to tell my computer to run a program on fpga

Thanks, Im a foruth year in EE (were not touching FPGAs or anythink practical...), I'm writing in systemVerilog, I know what FPGA is, I know how to program him, but the idea of how to make the cpu use the fpga as a slave , this is what Im missing..

Lets say I have an Ip on my fpga that allows me to use the pcie on my computer, and lets assume that I have a driver that let's my fpga use the pcie, from that point how do I tell the cpu to use my fpga as a slave.

Thanks.