To look inside the archive, you must use a specialized file archiver capable of unpacking the proprietary RAR format.
in global databases, software repositories, or threat intelligence networks.
Could you clarify this specific archive? Knowing its origin (such as a gaming forum, a work email, or a private database) will help isolate what you should expect to find inside.
Once the archive is safely extracted in your isolated environment, look for indicators to identify what the file actually is:
Look for .txt , .md , or .pdf files. They usually contain instructions, author credits, or patch notes.
Full text of "The Daily Colonist (1927-06-21)" - Internet Archive
Upload the file to an online multi-engine scanner like VirusTotal to check it against dozens of antivirus databases.