"My sister went to college " seems to mean she is still in college or she finished her college education,
while "My sister entered" college sounds like she has just passed the exam and is now a college student.
If someone is going to college, I generally go right ahead and say that he or she is going to college. I wouldn't say that he or she went to college (past tense) if that person is still going to college (present progressive).
If someone had just left home to go to college, then I might say, "She went off to college," just as we might say, "She went off to church." And it is fine, of course, to speak of someone entering college if he or she has entered college.
If someone has just been admitted to college, we can say that she has been admitted to college. In general, the phrases we use in relation to college correspond directly with the meaning. We can just say what we mean.