If you want to delete one record at a time then the code is basically the same as you have for inserting except the SQL code will change. That said, you should get into good habits now and start using parameters rather than string concatenation to build SQL statements. The resources in the Database FAQ thread provide examples and there's a link in my signature to a blog post dedicated to the topic.

Rather than editing one record at a time directly in the database, you might want to consider editing the data locally first and then saving as a batch. Again, the Database FAQ resources provide examples, including one in my own CodeBank thread.