Retaining Original Formatting and Restricting Entries

[Jaysin2011]

I am creating an excel template that users will mostly populate by pasting columns of information into the template from various other spreadsheets. I need to retain the formatting in the template, however when pasting from another spreadsheet, the format that was copied from other spreadsheets typically overrides the existing format in the template.

I know that you can use Paste Special -> Values so that the formatting isn't pasted over, however with the variety of users that will be utilizing the spreadsheet I am trying to make it as Dummy-proof as possible.

Additionally, there are certain fields that need to be restricted so that only certain, exact fields can be chosen. I currently have dropdown picklists in these fields, however they can be pasted over by the user.

Is there a way to make my spreadsheet retain the original formatting, even after a typical ctrl-v paste? Also, is there a way to make it so that only certain fields can be chosen, without being pasted over?

Thanks in advance for the help!