adapting code to merge the quantity for two columns and for duplicate items

hello
I have code works very well to import data for specific sheets from multiple files based on matching sheets names with file OUTPUT . I need from experts to help adapting the code or alternitave .
I would merge duplicate items based on column B and summing values in column F,H with the same formatting
so I put a little result into file OUTPUT how should merge and sum the values for specific sheets for all files .
note: the all files are existed in the same folder.
thanks