Display fields when selected particular value are select in backend module of typo3
Set on-change condition on checkbox or selection in typo3 backend module
For that first you have to add this line in your ext_table.php
'requestUpdate' => 'show_news',
show_news : You can choose those field name in which you need to apply on-change condition
After this you have to set below line in your tca file where you have set display it on such condition.
'displayCond' => 'FIELD:show_news:=:1',
You can easily get all thing from attached image.
If you have any queries, please do not hesitate to contact me at Jainish Senjaliya