you need to know the app id of pico store to open the app page in stroe, and you can ask the id of pico store by sending email to picodevanswers@bytedance.com. Here is the code.
public void LaunchStoreDetail()
{
AndroidJavaObject context = new AndroidJavaClass("com.unity3d.player.UnityPlayer").GetStatic("currentActivity");
AndroidJavaObject intent = new AndroidJavaObject("android.content.Intent", "pvr.intent.action.ADAPTER");
AndroidJavaObject intentEx = new AndroidJavaObject("android.content.Intent", "picovr.intent.action.storedetail");
intentEx.Call("putExtra", "intentextraappid", "(your app id in store)");
intentEx.Call("putExtra", "intentextratype", 2);
intent.Call("putExtra", "intent", intentEx);
intent.Call("setPackage", "com.pvr.adapter");
context.Call("startService", intent);
}