I\'m basically trying to construct a query, and I don\'t know why microsoft made this so difficult in Entity Framework and LINQ. I have various parameter STRINGS. So if you
this should be incredibly easy and simple for a modern language
No, it should not if it goes against that language paradigm. LINQ and Entity Framework (as well as any other decent ORM out there) are made precisely to avoid what you're trying to accomplish: non-typed and non-compiler-verifiable queries. So basically you're forcing square peg into round hole.
You can still take a look at Dynamic LINQ.