Black spots are generally caused by over-watering, sunburn, or sometimes bugs. The spots won’t go away. Once a succulent leaf is damaged or scarred, the only way to hide the spot is to remove the leaves with spots. If the black spots are dry, it’s most likely caused by sunburn. You can remove the individual leaves, but it’s great that you’ve brought the plants inside. They’ll still need sunlight, but make sure that they’re not getting too exposed.
If the spots are mushy, it’s probably from over-watering. You can remove the leaves with spots on them and then repot the plant in dry soil. Wait until the soil is completely dry before watering again. You should be able to adopt a watering schedule that should help keep it healthy.