When you go away from one place and start going to another place, use LEAVE FOR:
- I’m leaving for Beijing tomorrow. (I’m going away from home and go to Beijing.)
- When are you leaving for work? (When are you going away from home and go to work?)
- The plane leaves for London at 10 am. (The plane leaves the airport and starts flying towards London at 10 am.)
LEAVE somethig/someone TO somebody means giving somebody the responsibility to take care of something/someone:
- You can leave the cleaning to me, Jeff’s doing the cooking.
- I can’t deal with Mr Jones anymore. I think I’ll just leave him to you.
- I have no time to finish this report. Do you think I can leave it to Tim?
Also, use LEAVE something TO somebody when somebody wants another person to have something after his/her death:
- Tom left his house to his daughter.
- He didn’t leave anything to his son.
*note: LEAVE TO is not used with places. Use FOR when talking about where somebody is going.
LEAVE may be followed by TO + VERB when saying WHY you are leaving:
- I’m leaving to start a new life.
- We have to leave to get there on time.