Which windows server to choose and what to put there?

Question

Active Directory

Hello.
The company has 24 users. I want to install a windows server and do the following on it:
1. Enter all computers into a domain, divide them into groups, and create a group policy for each group.
2. Deliver mail, which will have the following features:
a. Preservation and storage of all incoming and outgoing messages;
b. Creation of groups (accounting, workers, etc.) to send a letter to everyone in this group at once, and not to choose the address of everyone;
c. General address book (added on the server and this address appeared for everyone);
d. Incoming and outgoing emails were downloaded on other devices under the same account (ios, android and windows), and also saved on the server when sending/receiving emails on these devices.
3. In the future, it is possible that the server will have desktops of users who will connect remotely from weak computers.
What server is needed for this, what windows server to install, what mail, and maybe something else you advise?
UPD: I would like to connect and configure all this myself, so that there is an experience.