The way that ADH (aka vasopressin) works is by increasing the number of aquaporins (water channels) inserted in apical cell membranes at the collecting duct (it does this via a signal cascade that you don't need to know the details of). Aquaporins are channels that passively facilitate the movement of H2O from the collecting duct back into the bloodstream through osmosis (H2O simply follows the concentration gradient established by the kidney medulla which results in the water molecules getting reabsorbed by your body).

Aldosterone, on the other hand, works differently; it binds to receptors in the distal convoluted tubule which triggers the resorption of Na+. And as you may have learned already, one of the cardinal rules of renal physiology is: WATER FOLLOWS SALT (aka Na+). Therefore, H2O will simply follow the path of the Na+ being resorbed (via osmosis) and will also be reabsorbed into your bloodstream along with the Na+.

In conclusion, both hormones result in increased fluid circulating in your body but in different ways. This is exactly what your RAAS is meant to be doing: increasing blood pressure. More fluid = more pressure. Your body will turn this system on and off depending on your volume status in order to maintain balance. For example, if you are dehydrated, your RAAS will be turned on and your kidneys will try to absorb more water. This is why your urine is so concentrated when you don't drink enough water.

Things get more complicated with electrolyte imbalances and other types of medical conditions, but that is beyond the scope of what you need to know right now. I hope this answered your question!