Hi @maheshkhisteLiv,
Do you want to extract properties for 300 files and put them into a single Excel file?
You said that every Excel has 2 sheets, my understanding that one sheet will be used to store the file properties, how about another one? Do they have the same format?
To merge into single Excel with 2 sheets, you will need to get rows from one sheets, then add rows into another table.
I have made a flow likes below, please check it for a reference.

Best regards,
Mabel