Venomous Idol

I need help making a datapack for minecraft - this is for a cursed item I wanna spice up my upcoming SMP with. A totem that grants conditional immortality.
> Instead of a yellow and green firework explosion like the regular Totem does, it's all red.
> When you die with the Idol in your inventory, you are revived with Strength 4 and Speed 3, but it halves your maximum health. A countdown for 3 minutes starts, shown as red text above your HUD, along with a progress (0/8) kinda thing alongside it.
> Kill 8 things during this state, and your health is restored to full, the countdown stops, you're all back to normal, but your strength and speed are removed.
> If you fail to kill 8 things, you are struck by lightning and immediately killed, and the countdown stops as a result.
> The idol is created by dropping the following things on the ground: A totem of undying, 64 skulls, 64 wither skulls, a lingering wither potion, a lingering regeneration potion, 64 spider eyes, and a nether star. It appears in a red firework explosion where the items once were.
>For now, the totem texture for this specific item is replaced with that of an enchanted fermented spider eye, but I plan to have a custom texture for it soon.
I have zero idea how to make this, and I'd like some assistance with it (not making it for me, I want help making it myself, like guiding me through things.) I want it to not conflict with other datapacks.
I'd really appreciate it, thank you so much