idiom
a brave face
jab aap waaqayi dar ya chinta mehsoos kar rahe hote hain tab sahasi hone ka naatak karna
Meaning
to pretend to be brave when you are actually scared or worried
Example
She put on **a brave face** despite feeling nervous inside.
Usne **ek sahasi chehra** lagaya, bhale hi andar se wo chinta mehsoos kar rahi thi.