Update en docs

ydb/docs/en/core/yql/reference/yql-core/builtins/_includes/basic/variant.md

@@ -95,3 +95,22 @@ SELECT
 ;
 ```
 
+## Way {#way}
+
+Returns active field (active index) of a variant over struct (over tuple)
+
+### Signature
+
+```yql
+VariantItem(Variant<key1: K1, key2: K2, ...>{Flags:AutoMap})->Utf8
+VariantItem(Variant<K1, K2, ...>{Flags:AutoMap})->Uint32
+```
+
+### Example
+
+```yql
+$vr = Variant(1, "0", Variant<Int32, String>);
+$vrs = Variant(1, "a", Variant<a:Int32, b:String>);
+SELECT Way($vr);  -- 0
+SELECT Way($vrs); -- "a"
+```