I need to find out how to limit the number of characters that can be entered
in cells within a certain column. Ideally, a message box would pop up if
someone tried to enter more than 30 characters and direct them to split the
data into the adjoining column.

The limit is necessary to allow import into a vendor's database. Two fields
are limited to 30 characters each. Any characters beyond 30 would be
truncated upon import.

Can this be done through a macro? Or would I need code to accomplish this?
I am a novice, but can create some macros and wade through some code.