The succulent looks like it has had too much sun or water. It needs to be watered when the soil is dry and needs at least 5 hours of sun a day.

you might be watering too often.

I have purchased some indoor cacti and all of them are having issues with them browning.

I used cactus soil, they are placed by the window often, I water them.

Some of the roots also appear to be rising to the surface of the soil?