How can you tell the difference between fines lines and wrinkles? If you put castor oil and lines not visible does that mean its fine lines?

Matter of degree. If you are concerned about fine lines and wrinkles in your overall age management best to see a plastic surgeon for potential treatment options for each. Peals and laser resurfacing and Botox may help with the finer lines. Botox, fillers and more aggressive resurfacing or even facelift or blepharoplasty may be required for the deeper wrinkles. Best to consult your local plastic surgeon to discuss.
Yes you can. Fine lines are visible when you stay very close to the mirror or use a magnifying one. Wrinkles are much more visible.
Depth. Primarily based on the depth of the lines.Deeper wrinkles are long standing and more prominent with camouflage .