Blockchain network in java on NETBEANS

Create a program in java that has 5 services which those services are: 1. General diagnosis 2. heart diagnosis 3. Dentist appointment 4. Skin therapy 5. Diet information The program at first will take users. As much as we want It willl the user name, user id, and the service that we want for the user. And this will be a registeration Now every 3 registerations the program will create a block and then it will work with blockchain technology For the registeration to be uccessful it must include only the 5 services and the name and id (3 numbers) must be valid. Now with the creation of 3 blocks the program has sto start the mining process with difficulty level 3. we can create as many blocks as we want. with the block mining process finished the program has to print : block hash, previous block hash, data in the block, timestamp, number of guesses ή nonce THE PROGRAM HAS TO BE ON JAVA IN THE PROGRAM NETBEANS!!!!! I've uploaded a blockchain tutorial to show to you about how i want the blockchain to be done. Also i have uploaded a word file which is the pronunciation of the project but is for those who can read Greek language. I hope you can help me! ;)