Powershell Script to manage creating users account, and Mailboxes from Excel .csv file. -- 2

Need help with creating a very, very clean working powerShell that can. 1. check .csv file for duplicates user 1st and last name, and remove duplicates, then export a new excel .csv file that has been clean of duplicates. 2nd. From the new clean excel .csv file, 1st Check Active Directory to see if users already have an account created in Active Directory, if so, place the users in an excel file name ( UsersAlreadyInAD), and if not in Active Directory, create the users an Accounts in Active Directory, and place the users in the assigned OU / PrimaryAfflliation Group assigned to them in the in [login to view URL] file in Active Directory. 3rd. Check if Mail in ExchangeOnline Exist for users in the .csv file, if mail box exist, place user in Excel file name (UsersAlreadyHaveMailbox), then have script continue and create users Mailboxes that don't have Mail in our ExchangeOnline (Office365 Environment). 4the, have script email user's the new email with a create password with it being at least 12 mixed charters, and a link within the email for users to use to login to the mailbox, and a custom message area, and after script completes, have it print out a report of all accounts successfully created to a pdf file with the current date and named "03_7_21NewUsersAccountsReport" If I am missing something, do advise me, but this is basically what I need and i need it by Thursday Evening 3/5/21 Break script into parts running one section of code at a time, with clearly comments that explain what's happening at each stage of the script, clean up script. Need for Mailbox to be setup and an email sent to me of the users that got account mailboxes setup and email to the users letting them know their accounts are ready along with upn login and temp password and custom message I can send along with the email.