Pill confusion

I’ve Never used pills before always been on the depo shot it’s so easy. But I thought I would give the pills a shot. This might some silly but idk when to start them. At the moment I’m on the third day of my period. My period only last 5 days so I should end on Thursday. The package has 7 placebo. Do I start with the blue pills on Friday?? Last question when is the best time to take them or does it really matter?TIA I know this is very silly.