Update Readme.md

Readme.md

 # ProtoBuf
 
+## Generating Classes
+[Download protoc](https://protobuf.dev/programming-guides/proto3/#generating)
+```
+./protoc --proto_path=src --java_out=.\src\main\java .\src\proto\student.proto
+```
+
+## Results
 ### Data as json (RestF)
 [name: "Mohamad"
 age: 40
@@ -16,7 +23,7 @@ age: 40
 
 
 
-### Ref 
+### Useful Link 
 * [Why GRPC? How protobuf empowers GRPC?
 ](https://www.youtube.com/watch?v=9ttYs4dXc9k&list=PL1F54YqZCTdxpGWMM7zyOigOQ_MVwSNc2&index=2&ab_channel=BetterDevwithAnubhav)
 * [How Protocol buffers help GRPC | Code Tutorial | Java](https://www.youtube.com/watch?v=UAZ5Y9gay30&list=PL1F54YqZCTdxpGWMM7zyOigOQ_MVwSNc2&index=3&ab_channel=BetterDevwithAnubhav)