Update 'README.md'

README.md

@@ -1,2 +1,16 @@
 # fastapi
 
+```
+pip install fastapi
+pip install uvicorn
+
+
+from fastapi import FastAPI
+
+app = FastAPI()
+
+@app.get("/")
+async def root():
+    return {"message": "Hello World"}
+
+```