Microsoft and other software vendors often offer excellent free online training for their products.  If you're looking for training on a particular software product this free training may be all you need.

Microsoft Office Suite Office Training Center
  Office basics
  Be more productive at work
  Word
  Excel
  Outlook
  PowerPoint
  OneNote
  Access
  OneDrive for Business 
  Skype for Business
  Teams
   
Adobe Suite Adobe Support and Training
  Acrobat DC
  Photoshop
  InDesign