@Jukka_Koskinen Because I do not know what content your Excel file (workbook) has, I will call it a catalog, and assume that the data for this catalog is on just one spreadsheet (worksheet) named Catalog1.
The text of the "hand made list of goods" (product codes? or product names?) probably should be copied and then pasted into its own spreadsheet -- whether that spreadsheet is in the same Excel file as Catalog1, or in a separate Excel file. (It is a little easier to work with them if they are in the same file, but it might be safer to keep them separate; you can choose.)
But it is difficult to describe how to "delete unnecessary info" as we don't know which data exists, which data you consider necessary and which you consider unnecessary. It would be best if you could attach your Excel file, or a modified copy of a portion of it (better to keep certain info secret from business competitors, etc.) to your reply. Then we can see which spreadsheet columns contain the data you will describe, which will allow us to write the Excel formulas.
As you start to reply, you will see a link to allow you to do this (I put a red rectangle around it in this first image):
Then your browser window will change. Then, beneath the area for typing your reply, you can see in this image how to attach a file:
Please also mention in your reply which version of Excel you are using; for example, what you see when you enter these three Excel formulas into three empty cells:
- =INFO("System")
- =INFO("OSVersion")
- =INFO("Release")