Hi Patrick, I am a behaviour consultant and write for Wamiz. To encourage your cat to use the scratch post, I would recommend the following tips:
Cover your furniture to protect it, and start by placing the post where the scratching behaviour was happening.
Encourage your cat to engage with the post, playing near it with a cat toy or exciting treat. Cat nip or an enticing spray such as FeliScratch may help spark interest in the post. You can dangle the toy near the post to encourage your cat to reach and touch the post.
Reward all interactions with the post over multiple sessions, and repeat the games/treats regularly so the post signals good things.
It's worth noting that some cats don't use the post because of the following reasons:
The post may be in the wrong place - cats typically don't like posts hidden and out of the way.
If you have multiple cats in the same household they will need one each plus and extra one, as they use the post for marking their territory.
The material and size of the post is important - it should be sturdy enough for deep scratches, not wobbly, and tall enough for the cat to fully stretch it's spine.
Good luck with the training!