1>Expecting to find a type to be declared in a module rules named 'GSRuntime' in UE5Rules, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null. This type must derive from the 'ModuleRules' type defined by Unreal Build Tool.

I keep getting this error when I try to build my project. Any ideas on how to solve it?

Hello

Try to copy/paste the GSRuntime directory located in the engine (for example: (C:\Program Files\Epic Games\UE_5.3\Engine\Plugins\Marketplace) to a Plugins folder inside your project ( (Yourproject\Plugins). This should solve your issue i hope
regards