Add document

Package.swift

@@ -113,6 +113,7 @@ wamrTargets += [
 let package = Package(
     name: "WAMR",
     products: [
+        .library(name: "WAMR", targets: ["WAMR"])
     ],
     targets: wamrTargets + [
         .target(name: "wamr-demo", dependencies: [.target(name: "WAMR")]),

README.md

@@ -1,3 +1,28 @@
-# WAMR
+# wamr-swift
 
-A description of this package.
+Swift WebAssembly runtime powered by WAMR
+
+## Adding wamr-swift as a Dependency
+
+To use the wamr-swift library in a SwiftPM project, add the following line to the dependencies in your Package.swift file:
+
+```swift
+.package(url: "https://github.com/swiftwasm/wamr-swift", from: "0.1.0"),
+```
+
+
+## Example
+
+```swift
+import WAMR
+import Foundation
+
+let inputFile = CommandLine.arguments[1]
+let binary = try Array(Data(contentsOf: URL(fileURLWithPath: inputFile)))
+
+WasmRuntime.initialize()
+let module = try WasmModule(binary: binary)
+module.setWasiOptions(dirs: [], mapDirs: [], envs: [], args: [])
+let instance = try module.instantiate(stackSize: 64 * 1024)
+try instance.executeMain(args: [])
+```