Is it ok to have one C+ on your final transcript as a freshman?

I am a junior (rising senior), and from what I've seen on admissions material, colleges will not reject someone because they got a c as a freshman. It is definitely not the end of the world.

However, I suggest you start thinking critically about your classes - for example, if this math class you got a C in is advanced or if you had to skip a grade to be in it, consider slowing down a notch and find a class that is your level of difficulty. If you believe that this class is right for you yet you are still struggling, seek help from your peers (yes most of the time the smart kids will even teach better than the teachers themselves) and teachers.

Remember, school is not that hard as long as you study and try your best, and colleges are not trying to sabotage you. If, at the end of the day, you tried your very very best, and you still got a C+, explain to the admissions how math is just not the right class for you (there's an "additional information" essay section) and how maybe (say COVID) circumstances didn't allow you to find the best conditions possible to learn math, colleges will look at it and that it into consideration.

- hope all goes well for you