Hello there, I believe your post is not worded properly and it's hard to understand.
Are you seeking to commission someone or are you trying to promote your own services? Because if it is the second we're not allowed to self-promote or make Threads promoting sales on the forum, it's against the guidelines
The only way you're allowed to promote your services without getting in trouble is to expect someone to open up a thread in the "Collaboration" category and then, if they have clarified that they are looking to pay someone, you can drop your samples, contact information and prices. (But if you reproduce other people's artwork, copy/trace/highly-reference content, then it's likely you'll be ignored for the sake of avoiding any intellectual property / trademark / copyright issues)
Now, it'll be good that if you're going to repost other people's work on your social media, to properly credit them, the name of the original artist, a link to them or similar. "Credits to the artist" or leaving descriptions in blank do not support artists in any way possible, besides being a total lack of etiquette and disrespectful behavior against a person's time and skills.
BUT before reposting other people's art make sure to have the permission from them to do it, a lot of artist don't allow nor like their content being reposted by other people, especially without proper credit. So ask for permission before doing anything that is not solely yours, learn when no means no in case you get your petition rejected and just because something is on the internet, doesn't mean is free to use/repost.