Hi! I’ve been trying to raise a couple plants in my apartment but I don’t have much of a green thumb. I recently had these two succulents given to me but don’t know exactly what they are and I’m not sure if Im caring for the correctly. Any help would be appreciated.

Both were received about two months ago and have been transplanted with Schultz Cactus soil. I water them every 2-3 weeks until the water starts to overflow into the tray. They’re placed about 1-2 feet away from a South-east facing window. I live in WI so it’s pretty cold outside but the apartment is kept around 72F.

Plant One: • Leaves on the bottom seem to wither or die •The other day I picked off a leaf that was somewhat thin and translucent •It doesn’t seem to be rooting into the pot •It’s very loose and can easily be knocked out

Plant Two: •Has rooted lower than the other one • Does move a little but has a larger root system •The tips are dark purple/brown or even black

Thank you for your help!!

https://imgur.com/a/3ofACys