Genre replacement

I have searched for an answer and apologize if this is somewhere on the forum. I am a total novice to this script language but hope it can be done. I have a simple Genre list requirement for my car radio for driving safety reasons. Right now my audio compilation has some random Genre classifications that are not wanted and generated by another program. It was hit and miss when I ran my songs through the program.

I am hoping that there is some way with a script that I can select an artist and then it write the Genre for those multiple songs on my disc just by entering just two items- therefore enter the Artist and all of their songs are populated with the same Genre.

e.g. Artist Elvis Presley Genre Pop Artist Carrie Underwood Genre Country

I only have around 4K songs but I have tried doing them one at a time and although doable its taking forever. It should be a simple string replace on those files but doggone if I can figure out how to do it.
Thanks in advance for any assistance you can provide.

MP3tag has no mechanism to take one record and make it the master for all others.
The usual way would be:
Load your files
Sort them by the column ARTIST or filter them e.g. with
%ARTIST% HAS Presley

Select all files that should get the same genre
Enter the new genre in the tag panel
Press Ctrl-S to save the modification.

Perhaps you should preserve the original genre in a user-defined field as it is rather hard to get the appropriate genre back again.
And in general I do not see the direct benefit for driving safety with unified genres. But that could just be me.

I myself don't care much abot genres because genres are just boxes that seldom fit.

Anyway, what you should think about is that genres are classifications of music and not of artists or albums.
One artist can record music in several different genres, even on one album.

I understand what you are saying and can appreciate the logic. I think I have found the solution based upon another reply and will use the tag replace function.

Thanks for the replies- I appreciate it greatly.