The rules for specifying the address are the same as in the page settings:
when specifying an address without a slash (for example, homepage), the page will open at the address of the domain or subdomain without specifying the address of the page (for example, school.yogafindyourbalance.ru);
when specifying an address with a slash (for example, /homepage), the page will open with the full address indicating (for example, school.yogafindyourbalance.ru/homepage).
It should considered that sending mailings in the account is possible only on behalf of one domain.
All mailings by default will be sent from a single email address specified in the «Account Settings» — «Mail» section.
Thus, students from different projects who are authorized in the account under different domains will receive mailings on behalf of one outgoing mail address.
But, when creating a mailing, you can either leave the sender’s name by default, or specify another one.