Course creation
Purple Pen is a standard freeware used to create Orienteering courses.
There are plenty of additional resources out there a quick google and or YouTube search will lead you to additional if the ones from the Purple Pen site are not to your liking or you want more information.
OUSA | Club Development - Course Design
https://orienteeringusa.org/resources/club-development/#design
Map sources
Map sources
Navigation Games | neighborhood-O | additional School & park maps
OUSA YMP | see map locator & latest maps section
NEOC | display of locations on Google maps
CSU | list of CSU maps on attackpoint
UNO | WCOC | ...