Home is always at your home switches. That is machine zero position. You should ALWAYS home your machine after power on, and after each emergency stop.
Offsets, that is another pair of socks
After homing, your machine is in G54 offset, which is initially 0, 0, 0. When you place your material on router table, you drive your tool to the lower left corner, or center of your material and zero your X and Y axes, then you lower your tool to the material surface, or top of your table, and zero Z axis.
These zeroes are your G54 offsets or G54 machine coordinates.
If you want to multiply your design, then you need to dig deeper in G-code, macros, ...