They can have fairly broad and powerful abilities as they wish, but only a limited selection are available for use by the PC. See p89 of Part Time Gods for rules on how to buy supernatural abilities with skill points.
Bonus Points (BP) can also be spent to
raise the character’s Attributes and Skills. Attributes cost 2 BP per level, while Skills cost 1 BP per level. Keep in mind that Levels 9 and
10 costs double for both Attributes and Skills.
Likewise, Attributes and Skills can be sacrificed to gain additional BP at the same conversion rate. Sacrificing counts toward the 7 BP maximum the character can gain.
So, if you want BP to spend on supernatural powers, you can buy them with enough skill points.
And see on p93 rules for this attribute.
The character has someone in their life who works for them or admires them. While they are not as important
as Bonds, they all play some irreplaceable role in
the character’s life. This Gift, unlike Bonds, can include magical beings or even other gods at times, but are usually mortals who simply follow the character. Followers are assumed to have 3 in all Attributes, but the Follower gains 4 skill points that can be for each BP spent to
reflect the skills they use to help the character. Note that highly-skilled Followers are a lot less
likely to accept being abused by the character, and poor treatment may lose the Follower entirely.
So, any supernatural abilities you need your supernatural followers or gods to use on their behalf they need to purchase at an appropriate cost. They could have other abilities or powers, but those are not accessible to the part time god with their follower bond.
Athena, say, may be willing to provide you with guidance on war, but unless you pay enough to purchase her fighting abilities, may not fight by your side.