Open your link and open Retail.
You will see linkhttps://support.google.com/merchants/answer/7052112?visit_id=637208828304391641-943013696&rd=1
This is Product data specification for Google feed for Retail.
You can create the feed file in .csv, .tsv, .xls, or xlsx file.
Open Feed Manager and open menu Feeds.
You will see the button "Add New" at the top right place.
You can create
Google XML - XML feed file
Google Adwords (TSV) - the same feed file in tsv format (with TAB separator).
tsv file is like csv file.
tsv file has tab a separator.
csv file has comma a separator.
Feed Manager allows to creatr any custom feed templates too.
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