So i was told that cleric's or rangers who worship Besmara can exchange hunter's bond or a domain.
i just want to check if this is true, i've seen the rule on the archives of nethys but not the d20.
second question these can use improved familiar and boon companion right?
Yeah, it's from the the Skulls and Shackles Adventure Path. It's probably not on d20PFSRD because it's from setting content related to a deity that's not OGL.
Both of those feats are a yes, although if you were a cleric giving up a domain you wouldn't need it because you're treated as full wizard for the familiar.
Here's the text in full at the bottom of the page, in case you wanted to refresh your memory: Besmara on AoN