Well just some general advice, since what you have to do right now is working on the basics.
So first, for the foundation. Never use a even block count when building walls, that makes building good looking windows and adding details impossible. So if you see the cobblestone wall with the spurce behind it as support for the wall put at least 3 blocks of "filling material" (in your case stonebrick) in between.
Now for the roof, in this case there is way too much cobble, it looks like it will collapse rather sooner than later. So your best choice would be a wooden roof with cobble as border and for details. The other reason for using wood in this case is the looks, cobble has a really messy texture that makes it perfect for use as "filling material", but makes it hard to spot details. The clay adds some variety but the cobble is to dominant.
Another thing I noticed is that this build is extremely small height-wise so you should add in a couple blocks to make it look less "heavy".
There are also a couple things you did well for your first time building.Its nice to see that you already use 2-Layers for building, 1 for the wall itselfs and a second for the decorations. The decorations could need some work though, hence I suggest using an uneven block count with at least 3 blocks. The combination of materials is also a pretty decent one and the ceiling inside looks nice too.
All in all you will have a long way to go till you are able to build an proper Regalian-Style, but if you keep improving your skills and put a little effort into it you can do it.