Annotation to tell null-checking a property is not null?

Consider this code (C# 12/.NET 8):

class Content 
{
   public string Value { get; set; }
}

class Something
{
    public bool IsOK { get; set; }
    public Content? TheContent { get; set; }
}

Something ProcessIt()
{
    var result = new Something();
    if (/*whatever*/)
    {
        result.IsOK = true;
        result.TheContent = new Content() { Value = "Hello!" };
    }
    else result.IsOK = false;
    return result;
}

string? DoWork()
{
    var something = ProcessIt();

    if (!something.IsOK)
        return null;

    return something.TheContent.Value; // Null ref warning CS8602
}

Is there any way that I can annotate the code anywhere to avoid CS8602 after if (!something.IsOK)?

I know that I can use something.TheContent! on each reference, but if I have many references, that's not very neat.

I can also do Content content = something.TheContent! and then use content for the remainder of DoWork. Maybe that's the way to go, but if there's way to tell the null checking system that "from now on (until it's modified) assume that something.TheContent is not null", I'd like to know...