The thing about making sourdough that I’ve always told newbies is that even if it ends up not looking great, it still usually ends up as perfectly usable bread.

A few notes for you:

• There’s a lot of flour on top. I’m assuming this is from heavily dusting whatever you are having the bread proof in. It’s a huge drag to have dough stick to your basket/bowl when you are trying to flip it into a hot Dutch oven. If you want to get rid of some of the extra flour on the finished product, you can brush it off before baking with a pastry bush. Alternatively, you can use something like rice flour that should absorb water better, so you can use less. The real pro tip, though, is to use stuff like sesame seeds, rolled oats/, etc, cause they won’t stick, and they add flavor.
• If you want to improve the flavor of the bread, a small percentage of a different type of flour goes a long way. I like swapping 10-20% of the flour for something else like whole wheat, rye, semolina, or a combination. If you add too much, it will change how the dough behaves, and you may need to adjust hydration, but especially if you keep it to 10%, it shouldn’t matter.
• Flat loaves have a few causes and a few solutions. It could be fermentation (initial and final rise need to be long enough, but not too long). Cold slows it down warm speed it up, so eventually you learn how to fit it in your schedule. Alternatively, it could be your shaping. I like to use coil folds because it’s easy to feel the dough progress, and it’s hard to over- or under-work the dough. Final shaping doesn’t have to be anything crazy, and you just have to strike a balance of tightening the ball up without knocking all the air out. Finally, it could just be insufficient heat especially in the first 10 minutes of baking. If you are using a dutch oven, make sure it’s well preheated, if not, put as much thermal mass in your oven as you can: random bits of cast iron cookware is what I go with. Pizza stones, too. Steam also really helps.