Over thinking first time parent. and IDC. lol

So my son is 8 months and I'm just not sure how much of what and how often I should be doing. I am a stay at home mom and I know/ am always engaging with my son I just wonder if I'm doing right? So here are my questions! 1) How much independent time should a 8 month old have if any and how often? 2) How much of the day should be spent playing with toys vs Face to face play like tickle make funny faces peekaboo ext. 3)Is it unfair to make small trips to the store everyday? Like I stop at giant eagle about every other day for food/dinner It gets me out of the house and it breaks up my long days lol. But I have began to wonder if this is selfish? It takes no more than a half an hour.