Cayenne pepper and red pepper flakes? Chili powder? Sorry for the double questions. I'm looking at two recipes of chicken tikka masala and one has both cayenne pepper (1/4tsp) and red pepper flakes (1/2tsp) I can only find red pepper flakes where I live. My understanding is that they're both made of the same kind of pepper. So, for this recipe would it be okay if I just add extra pepper flakes in place of cayenne?

The other chicken tikka masala recipe calls for chili powder (2tsp), which I think for Americans means a mix of several spices. (Where I live chili powder and red pepper flakes are the same thing) They don't have it here either. I found some recipes for chili powder blend but they require cayenne (again!) and onion powder, neither of which I have. So, what's a recipe for chili powder that has neither but still would taste similar to the original?

So, what should I do and which recipe should I use between the two that would yield a better result despite my lack of ingredients? Thank you in advance for your answer.
I've never come across anywhere where powder and flakes mean the same, but substituting one for the other should work in terms of flavour (the appearance and texture might be a bit different).

More specifically, in some places chilli powder means powdered chillies (like cayenne), in others it means chilli spice blend. Here in the UK it's even worse - both meanings can be found in the same shop.

Red pepper flakes aren't as common here as chilli flakes, but I wouldn't expect red pepper flakes to be hot, unlike chilli flakes. Sweet/mild paprika would be the substitute in that case.

So you have to be careful of where the recipe comes from as well as where you are. I suggest you have some form of mild pepper in powder or flake form, and some form of hot pepper, and adjust to taste when the dish is nearly cooked. This isn't perfect as (especially with flakes) the flavour needs to cook into the dish a bit.