What is the best way to send taxes to the refinance company.

The best way is to print them off; and then USPS mail, hand deliver or fax them.  I've never used the program at this link, but have heard good things about it:

The Acrobat Alternative (pdf-format.com)

You can also get a free Tax Transcript on the IRS website.  Most lenders will accept this.

Get Transcript | Internal Revenue Service (irs.gov)

Adobe Acrobat Reader is free. It can open and print a PDF.

Adobe Acrobat Reader DC

You can open the file that has your taxes in it and select 'Print'.  Then instead of selecting an actual printer, select 'Print  to PDF'.  This will then create a .PDF version of that original file you have that you can then save on your computer somewhere (desktop is easiest) and then email it to your refinance company.