No, you can't. That was a feature that got cut. The entirety of the "branching path" system is a series of 3 questions at the end of the game.
Side missions also affect eachother and some have hidden timers, if you don't complete an objective in time or don't check in with the NPC, things will happen out of your control.
Hell, if you manage to play the nomad side missions well and a particular NPC likes how you do things, you can get their gun. But if they don't like you, that doesn't lock you from the rest of the nomad options, you just don't get that gun.
For all the bugs that the game has, side missions and choices do affect things and the game makes a good effort on making you feel like it has more impact than it has (after all, a lot of it is simply a like/dislike score, but a lot of games operate on that scale), like some meaningless inquiry option (ie, blue dialog option) can lead you to a completely new dialog tree that can open up a small side mission in a different way.
I was already counting the "secret" ending. Two of the "choices" you can make without meeting the criteria are really the same ending with slightly different dialogue options. Mass Effect did not have multiple endings.
Side missions may have subtle differences but the entirety of the mission is in a vacuum; there's no difference between whether or not that trigger exists outside of that single event.
It led me to feel like a county fair more than a living world. "Next up, head to the torture booth! Ignore the wood scaffolding along the way".