When deducting mileage to a second job, if find the way the software is asking you to input your values are confusing, please clarify what each value should mean: Total

Here are the answers to your questions. With the commuting miles, be as accurate as you can, knowing that it's only the deductible miles you need to log.

Total miles for all purposes (I am assuming this means how many miles you drove last year): Correct

Miles driven for job (first job? second job?, mileage between jobs?, which one?)  In your example, the mileage between jobs. (Note: According to the IRS, if you go directly from your day job to your evening job, you can deduct the commute between those 2 job sites. But if you first go home and then leave to go to your second job, that can't be deducted.) From your second job to home is commuting.

Commuting miles, the miles you drive to and from your regular place of employment?  Typically, most people would use the first job for the year. Even though from your second job to home is commuting, this doesn't affect your taxes. Be as accurate as you can.

Round trip average daily commute: For simplicity sake (depending on how often you have a second job in the same day), a typical round trip from your home to your first job.

Here is what's deductible mileage:

• Your trip between your home and your regular or main job is never deductible.
  
• A trip between your home and temporary work location is deductible if your main job is at another location.
  
• Your commute between home and second job is never deductible on a day off from your main job.
  
• Your trip between your regular job and temporary job is always deductible.
  
• Your trips between your main and second job are deductible.
  
• Your trips between temporary work locations and a second job.