The only bonus that Hunt prey gives you on attack rolls is getting to ignore the second range increment to ranged attacks. Spell attacks don't have range increments, they just have a total range of the spell, so Hunt Prey does nothing to help with spell attack rolls.
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"Source Core Rulebook pg. 228
Archetype Ranger
Prerequisites Dexterity 14
You become trained in Survival; if you were already trained in Survival, you instead become trained in another skill of your choice. You become trained in ranger class DC. You can use the Hunt Prey action."
"Source Core Rulebook pg. 168
You designate a single creature as your prey and focus your attacks against that creature. You must be able to see or hear the prey, or you must be tracking the prey during exploration."
You gain a +2 circumstance bonus to Perception checks when you Seek your prey and a +2 circumstance bonus to Survival checks when you Track your prey. You also ignore the penalty for making ranged attacks within your second range increment against the prey you’re hunting."
Which bonus are you attempting to obtain?
The Hunt Prey granted by the archetype does not come with Hunter's Edge as well so most of the bonuses you obtained would not be applicable to spells.
However if you had a spell attack with multiple range increments I believe the spell attack would not be penalized for firing into that second/longer increment on a target you had Hunt Prey on. Most spells have a definite range and not a range increment though.