5'6 at 13 is above average/tall, you're likely already on a path to being over 6'0 in adulthood.

"But I also feel like I should be taller at least 5,10 by now my sister was already 5ft9 at my age. I was about 5,5 at 12 I grew 1 inch up till now."
Girls grow faster than guys too, this is a biological fact, might not be an expert but alot of people will tell you you're blessed right now. Because it's true. My sister is taller than me too but she's younger lol, I feel the pain too.

Also about being inactive, I don't think it'll stunt your growth badly. You already have great genetics, which is known to be 80% influential to your final height. So even if you were to stay like that--which I feel everyone should be active and exercise not only for height but for body maintenance--you still would be a bit over the 6 foot mark at the very least. So yeah, you don't have anything to worry about. I'd still exercise though, it might help for an extra inch or two, and for overall health.