@Entity
@Table(name = "MY_TEMPLATE")
public class MyTemplate {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID", nullable = false, updatable = false)
    private Long id;
    @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true)
    @JoinColumn(name = "MY_TEMPLATE_ID")
    private List<MyRsc> myRscs = new ArrayList<>();
    ...
}

@Entity
@Table(name = "MY_DAILY_RESOURCE")
public class MyRsc implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID", nullable = false, updatable = false)
    private Long id;
}

MyTemplate mt = new MyTemplate();
mt.setField1(someVal1);
mt.setField2(someVal2);
mt.setField3(someVal2);

MyRsc mdr = new MyRsc();
mt.getMyRscs.add(mdr);//!!!
mdr.setFfld1(smVal1);
mdr.setFfld2(smVal2);
mdr.setFfld3(smVal3);
crudRepository.save(mt);

@JoinColumn(name = "MY_TEMPLATE_ID", nullable = false)