Most of the time, yes, you do need an overlock foot for your overlocking stitch. Your machine may have come with one, or you may need to purchase one. Whenever you're buying afoot, make sure that the brand matches your sewing machine brand. But, the ladder stitch may be the closest in look to a serged edge.

Can you overlock on a normal sewing machine?

Overlocking on your sewing machine

You can buy an overlocking foot here. Line your fabric edge up against the guide and select either an over-edge stitch or a wide zigzag stitch. ... This protects the raw edge of the fabric to stop it from fraying or unravelling.

Why use a serger instead of a sewing machine?

Because of the multiple threads being looped together, a serger makes a more professional and durable seam than a standard sewing machine. The threads lock around the seam to prevent fraying, and it also has a blade that cuts off the seam allowance as it sews (the blade can also be turned off if you like).