Hi there!
You should be all set since you now have more than 10 posts (I just checked your account, and there was nothing for me to upgrade). So, welcome to Sweet Shoppe!
To answer your question, you won't be able to post an attachment in the forum here. All photos need to be hosted elsewhere.
Here's a tutorial on inserting your layouts into posts (if your layout is hosted in our gallery):
https://www.sweetshoppedesigns.com/t...-in-the-forum/
For other images, you can host them offsite on sites like imgur.com If you do it from there, you'll just want to copy the "BBCode" and paste it here. It will look like this (without the spaces)
[img ]https: //i.imgur.com/TcmCoGw.jpg [ /img]