Using circuit power supply to power relay load

Afternoon all.
Quick question, before i fry my latest project (or worse !) ...

I've just built this kit
with which i want to control a 12v car fan ....
Can i connect the fan to the same 12v power supply i'm using to power
the circuitry with the relay switching it on & off ?
Thanks in advance for your advise.
Pete.

As long as you use the relay contacts all the way to the right in the schematic, you can do anything you want with them, including putting the normally open relay contact in series with your fan. The relay contact can either be in the high-side (12V side), or low-side (to ground).

Ah lovely !
Thanks Mike.