Up to 60% of students entering colleges take some sort of remedial class. These classes simply get students up to speed and prepare them for the rigor of a typical college class.
Many students may want to avoid remedial classes due to pride or fear of it slowing them down, but someone who has been out of an academic environment for a while could benefit from these classes greatly. It is only natural to forget some of the foundations necessary to succeed in college-level classes.
Don't let fear or shame stand in your way of getting all the help you need to succeed in your classes. In addition to enrolling in a remedial class if recommended, approach the teacher after class for clarification on any issues you are struggling with, or enlist the help of a tutor. It's their job to help students, and they want to see you succeed!