Macro that will work on different sheets week to week?

I receive a spreadsheet every week from a vendor with different sheets for different product categories.
There are 20 possible categories that they will send me, but most weeks they will only send a random 10 out of the 20.
There's a lot of manual sorting I have to do so I created a macro to go through each of the sheets and do the sorting. But that macro only includes the categories they sent me that week. I tried adding in the other categories so that if the vendor sends me a spreadsheet that includes those, my macro will still work and not exclude anything.
However, I get an error message when I try running my macro because it's telling Excel to work on a sheet that isn't there. Is there some magical coding I can do to make this work with the changing sheets week to week?

Can I paste my code here so you can take a look?

I can't attach the Excel since it's full of sensitive information.

Right now this code is just going through each sheet and adding three columns to the end.

I tried adding this bit of code to the end of my macro, replacing "new" with the other possible names of sheets so if next week my vendor sheet includes one of those other sheets, I won't have to redo my macro:

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But once it gets to the portion of the code for a sheet that's not in the current workbook, I get an error message.

Is there a way to write the code so that it will just go through the sheet options and add the columns in if the sheet is there?