How to name binary ionic compounds?

the name for binary ##A_mB_n## is “A B-ide” or “A (Roman numeral) B-ide”
All binary ionic compound have a general formula of ##A_mB_n##
##A## is the cation or the metallic ion.
##B## is the anion or the non-metallic ion.
If the cation or the metallic ion is an element that can only have one charge (i.e. all the alkali metals and Alkaline earth metals in group 1 and 2 and some of other metallic elements) then you use the following method:
Write the full name of element ##A## at the front, leave a space, then write root word of the name of element ##B## then without space next to it write the suffix “ide”
e.g.
Na is sodium
Cl is chlorine . The root word of chlorine is chlor
Therefore NaCl is called Sodium Chloride
If the cation or the metallic ion is an element that can have more than one charge (i.e. lots of the transition metals in group 3 to 12 and so other ) then you use the following method:
Write the full name of element ##A## at the front, without space, write the charge of ##A## in Roman numeral in bracket, leave a space, then write root word of the name of element ##B## then without space next to it write the suffix “ide”
e.g.
Fe is iron . It has a charge of +3 in this compound.
O is oxygen . The root word of oxygen is ox
Therefore ##Fe_2O_3## is called Iron(III) oxide
This video might be helpful

You might also see some inaccurate way of writing it by using the naming rule for binary covalent compound.
In some old book you might see something like ferric oxide and ferrous oxide. That is old-fashioned. It is also more difficult to name and memorize the rule than the way we currently using.