We are moving from SharePoint 2010 to 2016, and we have a lot of InfoPath forms. We decide to Create new Farm for 2016 and start taking customizations, InfoPath and workflow one by one into SharePoint 2016.
My Question is What we will do for InfoPath and Workflow since are not supported in 2016?
Aside from official support, you should start thinking about the future taking Microsoft's roadmap and announced deprecations into account. If your future is on-premises there are no real alternatives other than 3rd-party solutions or custom development. If you are considering moving to SharePoint Online, you'll see that workflow scenarios can be implemented by using "Microsoft Flow" and PowerApps is generally considered (and positioned by Microsoft) to be the InfoPath replacement.