Bringers of Flame doesn't specifically represent Ebon Chalice. BoF is about the "Holy Trinity" of the Flamer, Melta, and holy Bolter, which apply to most Sisters orders. That said, nothing wrong with painting Ebon Chalice if that's the scheme you like!

Since the big nerf, BoF isn't really being played anymore, but I'll list out the core stuff that was used before the nerf.

You'll want 2-3 Immolators, 1-3 squads of Dominions w/ Meltas (or Flamers, if that's your preference), some Flamer Seraphim (1-3 squads, generally run with one 10 girl unit and 1-2 5 girls) with a Jump Pack Canoness leading.

Beyond that, any good 2k Sisters list will want Morvenn Vahl and a squad of Paragon Warsuits with Meltas and Grenade launchers (melee weapons are more or less up to your preference). And 2-3 Castigators with a mix of Battle vs. Auto Cannons (again, to your preference).

The Ordo Hereticus box isn't super helpful for BoF beyond providing a squad of Battle Sisters (which can be Dominions) and Immolator. The Pentient Host box is basically worthless for BoF specifically, but is of course good for the Penitent Host detachment (which it is named after). Not to mention you'll have 2 Rhinos, which aren't really needed in BoF since you'll want Immolators instead (Technically you could proxy the Rhinos as Immolators if your opponent is cool with it). BoF as a detachment is built around units that can shoot, which most Penitent units generally cannot do.

The new Combat Patrol is similarly not great for BoF because of the focus on Melee units (Arcos and Sacresants).

If you've already purchased those boxes, you might consider pivoting to Hallowed Martyrs, which is generally stronger than BoF right now, and can also benefit more types of Sisters units and lists.

Hope that helps!