Old Breaker Box

hey everyone. looks like im dealing with a breaker box that doesnt have a ground bar inside of it unless im completely blind and cant seem to find it. in this photo I see two bars one is up front at the bottom which looks to be the Neutral bar and there is a sneaky little bar under the breakers just behind this neutral bar, which could be the ground bar...but im unsure. I just need a little reassurance. the place that im living at currently is a old condo and the electrical box i believe was put in during the 70's or something like that. I currently own this property and i guess where im getting at is...I have a room that is about 30 feet away from the actual box itself. If you take a look at the picture all the breakers seem to be 2 pole. For instance I have 15/20 amp 120/240v 2 pole breakers, I have 20/20 amp 120/240v 2 pole breakers and at the bottom for the range i have 40/40 amp 120/240v 2 pole breakers. here is my question. Looking at this photo, I see 2 black wires going into the two slots for the 2 pole breaker. Now if correct me if Im wrong. I dont see any ground. If there using 12/2 wiring for 2 pole breakers wouldnt that mean that there should be a ground, 1 hot, and 1 neutral, or 2 hots one neutral? Because in this photo all I see is a neutral bar and both wires are plugged into the 2 pole. Now get this... If they are using 12/3 with the 2 pole its more understandable considering there ARE two hots in 12/3. there is 4 wires Red(hot) Black(hot) White (neutral) and bare(ground) this is why im confused..where is the ground wire if there using 12/3 and where is the ground if there using 12/2. Is there ground wire for 12/2 or is there just two hots and one neutral??? Im so confused cause all I want to do is replace one of these two pole breakers with 2 1 20 amp 120v breakers while running 12/2 from each into my grow room. I dont know why Im so confused but hopefully someone can explain this to me. Like I said replace 1 2 pole breaker, add 2 1 pole 20 amp 120v breakers and run 12/2 from both into my grow room with 20 amp 120v outlets....would seem pretty simple to do if i had a modern panel to work with but time has not been kind to this panel....please help! THANKS in advance.

hmmm nevermind about the grounding bar. correct me if im wrong but it looks like to the right of neutral bar there were some lugs hiding behind the wires that seem to have bare wires tightened down (could this be the ground bar) hmmm let me know thanks...if it is problem solved.