Hi a warm welcome to the site.
You can approach this assignment by collecting together the level 3 handbook your tutor has recommended along with any additional materials so you can research what positive attachment is all about.
You will also need to look at what happens in your setting/placement and identify the different ways you support children's attachments.
Search for
'positive attachment' in this amazon preview & click the link to page 102
Once you know what positive attachment is, the keyperson system and the impact of insecure attachments you'll be able write about it.
Hope this starts things off xx