Would anyone please show me whether there is any difference between the two?
to enter a school/college/university
to attend a school/college/university
Within this specific context, the answers by David W and OperaticSkeleton cover it.
Beyond the specific context of school, they can have very different meanings. For example, to attend a competition vs enter a competition. Attend would imply that you are a spectator, whereas enter would imply that your are competing.
Enter tends to be a sudden process, whereas attend is continuous. Especially in the case of a school, which is both an academic institution and a physical building, the meaning can be interpreted differently.
When using enter, you are most likely referring to the physical building, or the one-time act of getting admitted to study at a school.
- I need to finish an art project, I will enter X High School early tomorrow.
- I can't believe we'll be entering university next year!
This seems to be kind of a awkward or unnatural way to express this thought - I would rather use the verb to come in.
My partner Paul will be coming in early to help.
Expressing to enter as a noun, entry, sounds much more natural. However, note that it can refer to the physical sense or the academic sense.
- The school only opens at 7:30. I arrived at 6:00, so I was denied entry.
- Entry into Y University will require at least a 88% average.
When using to attend, you refer to enrollment as a student at that school, which could be for any period of time.
- I have been attending X High School for 4 years now.
- I didn't make it into Y University, so I will be attending Z College in the fall.
To "enter" generally refers to a student's initial attendance at a school as a function of age, eg "the boy was too young to enter college." As noted, it may also refer to the physical, literal entrance into a school building.
"To attend" refers to school attendance at any time, whether it is the student's first or tenth year to do so, eg "He received money to attend college."
There are contexts where the distinction might be less evident, but this generally illustrates the difference in the expressions.