Database Size error to restore to SQL Server express 2014
The backup is 7GB? What are the sizes of the MDF files before the backup? That is what Express Edition checks - it doesn't care about the size of the backup file, it cares about how big the data files are that it has to put on the disk. 

If this is for a production instance of SQL Server 2014 Express Edition, you're going to have to go back to the source and shrink those data files - it might be that they are larger than 10GB but not full, or it might be that you'll need to actually clear out some of the data.

If this is for local development, I suggest using SQL Server 2016 Developer Edition, which is free - and doesn't have any silly limits on file size.