Join and fetch in Hibernate Criteria API

Question

I'm currently working on my lab in university. My professor told me to replace long JpaRepository methods (like findXWhereAnd) with Criteria Api. I have multiple entities with different join conditions and fetch strategies, something like this:

@Entity
@Data
public class Parent {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @OneToMany(mappedBy = "parent", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    private List<Child> children;

}

@Entity
@Data
public class Child {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "parent_id")
    private Parent parent;
.
}

Now, I need to create a Criteria API query that fetches the Parent entities with their children list, while applying conditions on both of them.

How can I create such a query and avoid N+1 problem?

I've tried variations of criteria methods, but failed to understand how to do this.