Text: accidental deletion of important files while dealing with the unwanted one

Correct capitalization: Accidental deletion of important files while dealing with the unwanted one

Text: the minimum amount to deposit is 20 dollars or an equivalent amount in another currency.

Correct capitalization: The minimum amount to deposit is 20 dollars or an equivalent amount in another currency.

Text: the nazis start to come back.

Correct capitalization: The Nazis start to come back.

Text: infection of the body and/or brain

Correct capitalization:
Infection of the body and/or brain