Start at making a good user story for testing that defines what needs to be tested , and what is the expected behavior.
THen think of automating this task , just write down highlevel steps like ,
user should be able to delete an entry , given entry is present
Now make into lower level logical flow ,
1 . Create an entry
2. Delete the entry
3 Validate response
Now again split it into smaller once , how to create user , how delete etc. Again split it into smaller one , how to create post and delete request. How to fiteer a particular id from an array and so on.
COding is a tinny tinny part of programming world, design is the soul
you get coding answers by googling so don’t worry about it , concentrate on designing the test flow and use cases properly