Whilst we all are capable of making choices, Just because you make a choice that is good does not mean it's good for others and while making decisions that are morally evil to you maybe it's not as bad for others.
Yes you can make a choice on what you feel is good or bad, Unfortunately the rest of the world may not agree with your view over your beliefs on what is good or evil.
Everyone has their view on what good or evil is. So pays to observe and listen to their responses before you make a conscious decision on what you want to do in life.
Yes you are allowed to have a view on what is good or bad, Just like everyone else does, Whether you agree or others agree to your beliefs is another story.
And knowing what good and evil are, Prevents you from being evil. You can't choose to be evil if you are good, Because you know what evil is - that is, You know why you don't intentionally commit unjustified harmful acts to innocent life.
Bad people do not comprehend good and evil as evil is the absence of the knowledge of good therefore they don't really understand what evil is either, And this is why we call them bad people. They are indifferent to human suffering and have no issue causing harm to others to get what they want even at any cost to themselves (as in the end they will pay for their crimes, Either by man's law, Or nature's wrath).
Therefore, Good and evil are not merely choices we make, But are what we are. That is, We are either good or evil, We cannot become the other.
I cannot be someone else, This is not a choice I can make. You cannot be someone else, It is not a choice you can make. I am me. And you are you. While it sounds nice on the surface, This idea that we can all just choose whatever we want, It's simply not true. Facts are facts. Logic is logic. You can't argue with objective truth and expect to win.
For instance, Is it objective that there is no objective truth? Of course not. That argument defeats itself, Obviously.
OK so we are going to get into what the definition of good and evil are. We are going to get into how it's all relative. We are going to get into the free will discussion. Etc, Etc.
This topic brings in just about any semantics trick one could think of from both sides. If we all engaged in this debate we would never get to the actual question without a never ending argument about what defines good and evil and whether we have free will to make any choices. That's just two of many things that would lead us to the smallest micro organisms to religion (we all know how much we love beating a dead horse on that one - wink, Wink -) to space and beyond. We'd be debating whether a mushroom on a tree is defined as a good thing or a bad thing before we could possibly even try to answer. Is death bad and if so are we bad for picking an apple to eat. . . Is it good to wait for the apple to fall off the tree. . .
Unt uh - not me; no way. This debate is a trap and since I don't want to be here for eternity arguing semantics with you fine people I'm just gonna cheat and bypass all that and pretend we have free will for my own sanity and lets see here. . . Yeah the good and evil thing. I'm just gonna say we all agree on what is good or evil. And since the phrase is bias, Meaning the opposite of good is bad not evil, It makes choosing good to easy and bad gets skipped leaving only a couple evil deeds to ponder whilst thousands of bad deeds (which can be argued as evil but definitely closer to the evil side which that can even be debated) go unaccounted for. That right there in itself would wind up being a semantics nightmare for the people who will say Evil is Satan level stuff and you can't have a good bone in your body or else you wouldn't be defined as evil.
So my answer is yes we have a choice. We can be good people and do bad things. And bad people can do good things. We can also be good people who do good things and bad people who do bad things.
Knowing what good and evil are won’t prevent someone from being “evil” because what’s evil to you (whatever you define it to be) might be good to them. Good or Evil are relative terms created by men, Not absolute (what is good for someone might be bad for another). And thus, They are not who we are, Instead we choose one or the other (whatever they are defined) because they benefit us in one way or the another.