1. There's no simple answer to learning how to do something, everyone learns differently. For me, analysing the real thing is the main way to learn. Look at real wood. Look at real wood up close, look at real wood from a distance. What makes it look like what it is, even from a distance where the details aren't visible? What things are visible at different distances? Sometimes, it's just the interplay of colours, sometimes it's texture, sometimes it's many things. The curvy wood patterns are often not visible from a distance and are usually quite faint, so adding them tends to look exaggerated and might feel too cartoony for more realistic styles.
For distant wood like this, I instead suggest low-relief texture with some long lines of pixels like in my edit. It's pretty generic and can look like many kinds of textures depending on the context. The lines follow the direction of the texture - lengthwise following the generally lengthwise grain in wooden beams, but they could be horizontal, diagonal, etc depending on the texture and the orientation of the object.
2. I can't speak for HarveyDentMustDie and I didn't do anything with your colours, but in case you want another opinion on colour-picking:
Hue-shift more, and hue-shift consistently, that is, hue-shift your shadows all towards the same hue, and hue-shift all your highlights towards a second hue. This helps make the colours unified. HarveyDentMustDie's edit makes the shadows consistently more purple, and the lit areas consistently more orange/warm-brown.
Don't be afraid to exaggerate the coolness and warmth of colours, especially for interiors. Think more about how a location or object
feels or look at a first glance instead of worrying about the actual real colours of things. Wooden houses often feel very warm compared to the cooler colours outside, and accentuating the warmth of the browns helps convey that, even if in reality the colours would likely be quite dull.
HarveyDentMustDie's edit makes some subtle but important changes that aren't just palette-related: they make the tops of objects lighter, and the sides darker, which looks more natural because we're used to things being lit from above, and helps the tops (which are things we see best at this angle) stand out better. They also reduced or even removed many of your textures, because they weren't necessary and were harming the readability of some things.
I think HarveyDentMustDie's edit has some contrast and readability issues as well, so you still have plenty of opportunity to practice your colour-picking and colour placement
Edit: Not quite a colour tutorial, but
this tutorial on light is worth reading (it's multiple pages, don't miss the links to the next page at the bottom). Colour is the result of light, and understanding how light interacts with things and how it "carries" colour should help you choose colours more effectively.