How to avoid using the var data type in Asp .Net MVC5?

I have the following question and I want to know if you can help me clarify that doubt, it turns out that today ASP ASP.NET MVC5 is very much used variable type var which is a variable that adapts to the type of more convenient data, but I want to know how I can avoid using this type of data because first the compiler has to adapt that variable to the data type that returns the expression,

Thanks