How to create registration page with validation and transfer the data another activity in Android

MAIN ACTIVITY JAVA FILE

package com.example.pkchoudhary.registrationform;

import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.support.annotation.RequiresApi;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;

import com.google.android.gms.appindexing.Action;

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