Form 8949 for bad debt - need to attach supporting documents

I made a loan to an LLC for a real estate project. The LLC was unable to pay back the loan and part of the loan has permanently lost principal. As per Turbotax guide: https://turbotax.intuit.com/tax-tips/irs-tax-return/how-to-report-non-business-bad-debt-on-a-tax-ret...

 

It says that we can report the loss on Form 8949 Sales and Other Disposition of Capital Assets. However, the guide also says that we are required to attach a bad-debt statement to my tax returning, explaining the details of the loan I made. 

 

Questions:

1) How can I attach a supporting bad debt statement to my tax return using turbotax desktop version, home and business?

2) How much of the loan can I write off in a year, and can I write it off against w2 income or only against capital gains? 

 

Thanks much!