So, I hear people say blah blah blah is 3 light years away, and here's a photo. So does that mean the photo that we see are actually at least 3 years ago since that's how long it takes that light to travel to Earth for us to take the picture?
As the comments to your question say, the short answer is "yes". A lightyear is, by definition, the distance traveled by a photon in one year.
Note, however, that at large distances, the answer becomes more complicated. Due to the expansion of the Universe, the light received from a galaxy far, far away was emitted when that galaxy was closer to us. That means that in the beginning, the photons traverse a larger "fraction" of the Universe per time than at a later time.
Thus, to calculate the total pathlength you need to integrate its distance in an expanding coordinate system.
For instance, if a galaxy was a 4 billion lightyears away from the Milky Way when the Universe was only 1 billion years old, it is now 28 billion lightyears away. But as the Universe is 13.8 billion years old, the light received today from that galaxy has been traveling for "only" 12.8 billion years.
Objects in our local neighborhood, however, such as stars in our own galaxy and the nearest galaxies (e.g. Andromeda) are gravitationally bound and thus "resist" the expansion of space, so here your assumption is correct.