his can refer to someone's possession or belonging, such as in the phrase 'his book.' It can also be used to refer to kinship and familial relationships, such as 'his father' or 'his brother.' In general, his indicates a direct relationship between a person and the object or person being referred to, rather than an indirect one like 'a book of his.'
When his is used in the possessive form, it is always followed by a noun. When used in the family context, it is always preceded by an appropriate family descriptor such as father, brother, etc. When relating to familial relationships, it is always followed by a pronoun, such as 'his mother' or 'his Aunt Emily.'
1. 'The kids gathered around to admire his new puppy.'
2. 'His wife made a delicious dinner for the family.'
3. 'His teacher was impressed with his fast turn-around on the project.'
Make sure the word used are gender-appropriate, as many people prefer to use 'their' adjective as a part of gender-neutrality.