How can I use "in case of" please provide some examples.
Some examples for 'in case of':
'In case of an emergency, please ...' (hotel sign)
'In case of adverse effects, please follow ... advice.' (medication)
In more formal English situations it is also very common to see 'In the event of'
eg on an aeroplane 'In the event of emergency ...' which would be the same as 'In case of an emergency ...'