Please Help Beginner ----->Engineers

Please Help All Engineers ------>as I am a Beginner

😔It is regarding Connectivity and Practical knowledge
I need to create ATM project(i am sir not asking for project)
I have created Basic layouts of ATM using java applet in Netbeans IDE.
for login 1 applet,2nd for withdraw ,3rd for deposit,4th for saving and etc
So sir i want that
if i click on OK button of login(when i run that applet) it should go to next applet on withdraw

And other thing is that i have made database on MSaccess so i want to have connectivity between this applets and DB(means i have done setting on administrative tool)but I don't know to connect applets to DB through it's coding so that if i click on log in button it checks on DB that this user is authenticate user and if not then i will show alert box(log in failed due to wrong )

in same way i log in and click on withdraw button it should check whether minimum balance is there or not and if it is then it should with draw and make changes to DB amount section

This are my applet screenshot
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Please Engineers help starter engineer so that i can have understanding of what actually We are.