You can use the official WinRAR software or free alternatives like 7-Zip . Simply right-click the file and select "Extract Here" or "Extract to folder".
On DLsite, every product is assigned an "RJ" number. Searching for "RJ01313038" on the platform will typically lead you to the official product page, detailing the creator (circle), voice actors, and content description. H-RJ01313038.rar