Isolation and quarantine are terms used interchangeably but have slightly different meanings and intents when it comes to trying to control an infectious outbreak.

Isolation is for the people known to have acquired a disease.

If you are confirmed to be sick with a disease, it’s important to get you away from people who are healthy. It’s best to be placed in isolation to separate yourself from healthy people to prevent them from getting sick.

In hospitals, you know you’re in an isolation room just from how the air pressure is regulated lower than then the air pressure outside the room (or wing). When you come from the outside into an isolation room, the door is hard to open and when it does open, a rush of air is sucked in behind you to prevent any respiratory droplets from going outside of the isolation area.
Quarantine is for healthy people known to be exposed to a disease.

Quarantine is designed to restrict the movement of people who are well but have been exposed. People who are known to have been exposed can walk around freely while in quarantine but to not come in contact with others. That’s why it’s recommended that basketball players who came in contact with the one player found to be infected were immediately recommended to go into a self-quarantine.

Quarantine is almost like a house arrest because you are free to enjoy the luxury of staying at home, but for 2-weeks you are not to come in contact with any other people, unlike being in isolation where you are already sick, probably getting treatment, and are on lockdown from anyone except medical personnel.

You can go from quarantine to isolation if you develop an illness after being exposed. There is not a case for you to go from isolation to quarantine since you won’t be released from isolation until you are cured and safe to be among the healthy folks.