What's the matter? Do you want to restore your SQL database from the backup file or you want to repair SQL database? If you want to repair corrupt SQL database file, you should try Microsoft SQL Server Management Studio. This can help you remove your SQL database tagged as suspect. Read the blog post linked below for more information:
Repair SQL Database using SQL Server Management Studio | N.Sem's Blog
But if you want to restore your SQL database from corrupt backup file, you can try a BKF recovery software that supports recovery of SQL database from corrupt BKF files.
Thanks and best regards.