Switching to Craft from ExpressionEngine
You ask multiple questions at once – some of them quite broad. I'd recommend you create separate threads for each of your questions, and to try to be as specific as possible – e.g. elaborate a little on what you mean by "run multiple sites". That being said, in the event this thread isn't closed for being too broad I'll try to answer some of your main questions:


  Is it possible to run multiple sites using Craft?


Craft doesn't have an MSM-type feature, so short answer is no. See this thread for some further details and alternative solutions.


  Is there a plugin like Solspace Freeform for creating and managing
  forms?


Sure is. There's Sprout Forms which is a commercial, full-featured forms plugin, as well as a few free, smaller plugins such as Form Builder.


  How does site searching work. Would there be a way to tie this in to display local sites only?


I'd suggest you look at the official docs on searching in Craft, as well as the example search form.