There are many conflicts present in Mary Shelley's novel Frankenstein. Conflicts are presented in two different ways: internal conflict and external conflict. Internal conflict is the conflict which exists within a person or character (man verses self). External conflict is the conflict one faces with outside forces (man verses man, supernatural, and nature).
There are two main internal conflicts depicted within the novel. Both the creature and Victor face internal conflicts. Victor faces the internal crisis of bringing a dangerous being into the world. It is his desire to destroy the creature (given his personal feelings regarding his obligation to society and keeping them safe). The creature, on the other hand, conflicts with his own being. Given his obvious differences from others, the creature conflicts with his own existence (the whys and hows of who he is).
There are multiple external conflicts depicted within the novel. Not only does the creature face the frightened and aggressive society around him, he is forced to come to terms with the power of nature.
By degrees, I remember, a stronger light pressed upon my nerves, so that I was obliged to shut my eyes. Darkness then came over me, and troubled me; but hardly had I felt this, when, by opening my eyes, as I now suppose, the light poured in upon me again.
Given his lack of knowledge of nature, the creature fights against burning eyes, cold and heat.
Victor, on the other hand, conflicts with the creature (man verses man or supernatural--depending upon how one defines the creature). Victor, driven by the murder of William, Clerval, Justine, and Elizabeth, despises the creature.
“Devil,” I exclaimed, “do you dare approach me? and do not you fear the fierce vengeance of my arm wreaked on your miserable head?
As for the conflict of science verses nature, one example which illuminates this is found in chapter two. In this section, Victor is recalling the effects of a lightening strike on a tree. The lightening "utterly destroyed" the tree. Instead of being intrigued by the power of nature, Victor is intrigued by the scientific aspects which could be dissected because of the lightening strike.
Outside of this example, one could argue that another relevant example is the creature himself. The product of science, the creature is left to nature in order to learn and grow.
Everything is related in them which bears reference to my accursed origin; the whole detail of that series of disgusting circumstances which produced it is set in view.
Left on his own, the creature is required to fend for himself and learn about the ways of the world alone (surrounded only by nature).
Sorry, that didn't really answer your question.
In Shelley's Frankenstein, the central man-to-man conflict, if you want to call it that, from chapter 17 on is Victor vs The Monster, if you will.
Once Victor chooses to destroy the female and break his agreement with the monster, the remainder of the novel amounts to a "cat and mouse" game, with the monster being the cat. From that point on, the monster tries to kill everyone who's meaningful to Victor, and Victor tries to prevent him from doing so.
Once Victor fails to stop the monster, then the story is truly reduced to man vs. man, with Victor chasing the monster across deserts and ice and everywhere else in an attempt to get revenge.
Ironically, though, this great epic chase is at least in part a figment of Victor's fertile imagination. He doesn't stand a chance, and the monster certainly knows it. Taking the opportunity to mock Victor when he gets a chance, he actually leaves clues so Victor can keep chasing him.
The chase, if you can call it that, becomes the reason for both of their existences.
The effort of the monster to extract love from his creator the doctor (also the farming family) - which progresses to murderous extent as it is perpetually unfulfilled.