There's really no way to know for sure what breed a rabbit is unless it has distinctive breed characteristics or comes from a reputable breeder. So the lop is vienna marked, and could possibly be a purebred holland or mini(dpending on size), but presume it's a mix since you don't know it's pedigree. If the two rabbits are siblings, then they're definitely mixes.
The other rabbit, it's not close up enough that I can tell if it's a rex or not. If it's siblings with the lop, then definitely not pure rex, but a mix. If they aren't siblings, if it has a really dense plush coat that feels like velvet, then it's a rex. If it has a normal coat(like the lops), then it's unknown and presumably a mix.
Just fyi, if you don't know much about rabbits, at 10-12 weeks old, they'll need to be separated if they're male/female or male/male, or you could end up with a pregnant rabbit or serious fighting. If they are definitely both female(be careful because sexing mistakes can be made at that age), they may be able to be kept with each other a bit longer, if they're showing no signs of aggression or excessive hormonal behavior(eg. humping). Then find a vet that will spay asap. Though you do have to be very watchful, as fights can break out if one rabbit starts irritating the other with hormonal behavior, and/or aggression starts occurring.
https://rabbitsindoors.weebly.com/bonding-bunnies.html
https://wabbitwiki.com/wiki/Bonding_rabbits_together
http://language.rabbitspeak.com/
https://wabbitwiki.com/wiki/Spaying_and_neutering_rabbits
https://rabbit.org/vet-listings/