veeam backup basics

1) Does a veeam backup job typically constitute a 'Complete System Backups' – or is it highly configurable what the job will or will not include? E.g. could you restore the entire server (OS, App, configuration, data in a single restore operation), or does that require multiple steps?

2) Is there some form of screenshot on the veeam job properties which shows what specifically the job is backing up? I am a bit blind to the management side of Veeam Backup & Replication but need some supporting evidence from the admins for an audit.

3) Do you still do test restores of veeam backups, and what kinds of issues have you found that meant the veeam backups did not restore, or are they pretty 'faultless'? Not sure if the testing is quite an aged concept or still valid?