Not to deny that some of the MB standard refills do well with additions, but start simple before jumping into more complicated recipes. You will have a light beer, that is absolutely drinkable, without all the fuss of additions. Go to the deluxe refills, or seasonal ones for a more "hardy" beer. Then slowly expand your brewing. My humble opinion, YMMV.
Chlorine, can cause that taste as well as phenols from fermentation at higher temperatures. I now use spring or filtered water, and ferment at 64 -68 deg F (and even a little lower in the middle of the winter, like now). Unfortunately, that BandAid taste is persistent. Don't condition in the fridge. Only put what you plan to drink into the fridge a few days before consumption. Don't give up. Use the experience to improve your next beer.