The first place you can ask for help is the FreeCAD forum (Please read this post before asking any questions). There are different subforums for FreeCAD developers and users. Make sure you search the internet before you ask for help and read through the existing questions that have already been made and/or solved. There are also subforums, where you can discuss other subjects, give your impressions of FreeCAD, ideas, etc. The forums are very active and you should get a reply very quickly.
If you need help or have questions related to a particular page of this wiki documentation, you can always leave ideas or comments on the "discussion" tab of each page. To upload files for Wiki please use this page.
There is also an IRC #freecad chat room on freenode. #openFOAM-IRC is also on freenode. There are Discord servers for Modelica Language, Elmer FEM, and OpenFOAM. Please do not use chat groups as the main medium of exchanging data. They are not indexed by the search engines and information produced on those platforms is not accumulated, as it does on forums.
Twitter and Mastodon
You may join the FreeCAD's Facebook public group