Use dependency injection in static class

Solution 1:

You basically have two options:

1. Change the class from static to an instance class and supply IConfiguration through Constructor Injection.
2. Supply the IConfiguration to the Execute method through Method Injection.

Here are examples for each option.

Option 1. Change the class from static to an instance class

Change the class from static to an instance class and supply IConfiguracion through Constructor Injection. XHelper should in that case be injected into the constructor of its consumers. Example:

public class XHelper
{
    private readonly IConfiguration config;
    
    public XHelper(IConfiguration config)
    {
        this.config = config ?? throw new ArgumentNullException("config");
    }

    public TResponse Execute(string metodo, TRequest request)
    {
        string y = this.config.apiUrl;  //i need it

        return xxx; //xxxxx
    }
}

2. Supply the IConfiguration to the Execute method through Method Injection.

Example:

public static class XHelper
{
    public static TResponse Execute(
        string metodo, TRequest request, IConfiguration config)
    {
        if (config is null) throw new ArgumentNullException("config");
    
        string y = config.apiUrl;

        return xxx;
    }
}

Less favorable options

There are of course more options to consider, but they are all less favorable, because they would either cause code smells or anti-patterns.

For instance, you might be inclined to use a Service Locator, which is an anti-pattern. Ambient Context; same thing. Property Injection, on the other hand, causes Temporal Coupling, which is a code smell.