Currently there is no option in backend to clear cache.Instead we need to clear cache via command prompt.
There are two types of caches in Typo3 Neos.
1.Production Cache
To clear production cache use below command.
FLOW_CONTEXT=Production ./flow flow:cache:flush --force
2 Development Cache
To clear development cache use below command.
./flow flow:cache:flush --force
We have also command to clear particular cache
Example :
./flow flow:cache:flushone TYPO3_TypoScript_Content