Adding error handlers to your code is very import to enable you to fix errors that come up from users. This allows them to easily pass the info on so that the developer can fix. Without error handlers, the code will either skip the errors or just bring up a confusing pop of that the user does not know how to deal with.
Before adding any on error statements I suggest the user fully understand this article https://learn.microsoft.com/en-us/office/vba/language/reference/user-interface-help/on-error-statement
See the video below to understand a subtle issue that can occur in your code
Coding with Visual Basic 