i opened a dat file with notepad and there is just lots and lots of random letters and characters, What do i do from here to get the dat file in my rollercoaster tycoon? Like once i have all the letters and numbers where do i put it?

It depends on what you’ve downloaded.

If you downloaded a park you’d put the downloaded file in ROOT DRIVE:\Documents and Settings\USER NAME\My Documents\RCT3\Parks\.

If you downloaded a scenario you’d put the downloaded file in ROOT DRIVE:\Documents and Settings\USER NAME\My Documents\RCT3\Start New Scenarios\

or ROOT DRIVE:\Documents and Settings\USER NAME\My Documents\RCT3\Scenarios\

If you downloaded scenery or a building someone made you’d put the scenery item in ROOT DRIVE:\Documents and Settings\USER NAME\My Documents\RCT3\Structures\

After you’ve placed the file in any of these three folders you’d open RCT3 and access the object in RCT3 (open the file in RCT3). It is not possible to open an RCT3 scenario or park or to place RCT3 scenery in any application other than RCT3.