The second one is an Echeveria runyonii also known as 'Topsy Turvy.' I would not pot them together as they are all very different plants. It will be easier to monitor and nurture them if they're in individual pots. They each need a well-draining mix in a well-draining pot. The cactus and succulent mix you have will work well if you cut it with Perlite. A good place to begin is 50% Perlite to 50% soil mix. You can find Perlite at any nursery or Big Box store like Home Depot. It's relatively inexpensive. You can try beheading the stretched one. Let the cutting callous for a couple of days, then stick in the potting mix. Do not water it until you see growth. Keep the stem along with the pup. I'm not sure about this, so perhaps someone with more experience can chime in. When you do repot, add potting mix up to the top rim of the pot. That way your plants can get maximum air circulation. Good luck!

Hello, sorry can't ID as I don't grow these cacti. EL gives sound info above. As the first cactus is a tall one as opposed to a barrel shaped one, could I suggest that the best mix for both it and the other, would be a mix of thirds using c/smix, perlite and horticultural/alpine gravel. You can get small bags of each of these from B & Q for around £3 each. Make sure you either wash the perlite thoroughly in a sieve or just seive it downwind, don't breath the dust in. B&Q perlite is rather dusty, mine is, so there is a lot of waste, just use the largest particles you gain from using your very best kitchen seive! I've also used Wilko perlite, that wasn't quite as bad. Wilko may not sell it now it's Nov, B&Q or garden centres may be a better bet for all the ingredients at this time of the year. The gravel will give the plants much more stability, especially the tall one. Don't get vermiculite if no perlite, it's too water retentive. Aquarium gravel or chicken grit with no shell can also substitute for the hort/alpine gravel. Repotting into a better mix will get rid of any bugs that you think you may have there and it will also solve the problem that you almost certainly would be asking us about in the not to distant future "why are my cacti dying?"... which would be due to the wrong soil they were sold in! So, to prevent that from happening you need to make sure all the old mix is removed, use a chopstick, pencil or similar to get rid of it all. If it won't come if with poking and shaking, swish in water, keep bases of plants dry though, let the roots air dry on kitchen paper, plant when dry. Hold the cactus in a wrap of newspaper or bubble wrap to protect your hands. Moisten the mix and replant, not soaking wet, just moist and crumbly. Won't need much water anyway now weather is colder. Shout if you need any more help. Gill

That's actually 2 different cacti grafted together. Top part is Gymnocalycium mihanovichii, bottom part is probably a Hylocereus. There are many discussions in this forum, search for mooncactus care.

I can only ID the last one positively, it’s a Portulacaria afra variegata. Please don’t grow any plants and especially a cacti or succ in a pot without any drainage holes, and it’s not advisable to keep those glass pebbles around them either, they won’t allow the mix to dry out properly. The soil mix they’re in looks very peaty and water retaining, ideally it needs changing else you will get problems with rotting as from what you have said you are new to plants. Please change all the soil and replant in a simple free draining mix of half good quality c/s mix and half sieved perlite or similar. All need placing in a very sunny spot and the Port a. will need slightly more water than the others. Plenty of additional info if you type a suitable question in the search box at the top and tick to search the c/s forum, come back here if you’re stuck though. Gill