When the gender hasn't been identified, "they/their/them" must be applied instead of his/her him/her, such as your example, see:
Everyone applying for scholarship has to fill the form. He/She must also provide his/her result card with his/her form.
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Everyone applying for scholarship has to fill the form. They must also provide their result card with their form.
As "Everyone" is a non-identified gender, but it is considered singular, it explains the usage of "has", but if you answer goes along you will probably face the need of using non-identified genders, that's where "They/them/their" fit.
But, if you are telling a story, such as someone looking at your girlfriend or boyfriend, and you know who you were talking about, you could say: The last week's party was awesome, but there were some guys looking at my friend, she got really mad and left the party
"friend" is a non-identified gender, but it can easily be identified after you increased the "she", which implies to say that your friend was female.