Do I need to get instructions via the Magiceden api to send such a transaction solscanlink - link
Yes, every ME transaction needs to get signed by
NTYeYJ1wr4bpM5xo6zx5En44SvJFAd35zTxxNoERYqd as you can see on solscan. That means that you need to retrieve a partially signed transaction from ME via their API, which is heavily gated. You have to partially sign that transaction afterwards with the buyer wallet.