I currently have a relay set up with after market fog lamps and halo ring head lights with 3 LEDs in each set up to activate when i turn on my parking lights. I want to have them also turn on when I unlock the vehicle on the interior dome lights come on but not if I manually hit the dome light switch inside.

how can i achieve this?

 

Do you want them to just flash on and then off or stay on for awhile?

You could add another relay triggered by the Unlock power, it would power existing relay momentarily, this would flash the lights when door was unlocked.

Or you can get timed relays, same trigger using door unlock, but they have an adjustable "time" delay before they shut off, these require the trigger voltage and 24/7 voltage to time the event.

Either can be low amp relays since they are just triggering the high amp passing relay you already have for the lights.

 

I want them to stay on as long as the interior dome lights. I was thinking if i got a relay and had the relay activation terminal on that relay go to the lights circuit somehow then that would work. I just dont want the fog lamps to come on when i turn on the interior dome lights by the switch on the dash. Only by the unlock or door ajar

 

Tying in to the "light circuit somehow" is the issue.

autozone has alot of wiring diagrams you can access on-line, specific to Rangers by year.

You don't mention the year of the Ranger but it is most likely that if it is a timed circuit then that timer would be in the GEM(generic electronic module), located behind the radio.
The Dome light is on relay most likely but it would only have 1 trigger wire coming from the GEM, so the GEM would decide if it will be a timed closure(door unlock) or a fixed closer(manually turn on dome light), depending on which trigger was received, unlock or manual switch, so you would need to find that trigger BUT that probably wouldn't help because you would then need 2 relays, one to sense the unlock trigger to close the relay to the dome light, and that trigger is only momentary so you would still need the timer.

Best to just get a relay with built-in adjustable timer and match it to dome light timer.