There seem to me only three ways this crisis will end.
1. Some drug treatment is discovered which blocks the immune overreaction which is killing people by damaging their lungs. I see no sign of this although there are clinical trials.
2. After the current lockdown succeeds in reducing the numbers to a manageable level, the disease is allowed to work its way through the population until herd immunity is established. The studies on a few severely affected communities suggest that the first wave reached ca 15%, so it will take many months for this to happen. Most lockdown rules would have to continue all this time. (In Hokkaido, which had an early outbreak, they've just had to reimpose restrictions after a second wave began.)
3. A successful vaccine is created and is manufactured at scale. Not before this winter.
I see no way that significant international flights will restart this summer.