OP - I see that you are very new to the site (welcome, by the way). Just as a tip, it is generally considered poor form to create multiple threads on the same topic scattered around the forum. It makes it very difficult for those who want to help you follow the conversation when you have the same thread in three or four places and have gotten answers in all those threads. You may want to ask the admin team to merge your threads so that you and those replying to you can follow the conversation and you can get the most out of all the responses you might receive.
The conformation of horses matters anywhere from very little to a great deal, and in some cases IS a deal breaker for certain disciplines.
Have you spent ANY time reading about horses, learning about conformation, and where faults may lie? That is the best way to learn, rather than coming to a forum. You need to study it more in depth than just getting answers from members.
And that means having pictures to look at easily, descriptions of the various things, so that you can reference them quickly and study them until you have them firmly in your mind.
You can also do some searching of your own by utilizing the search bar on your browser and typing in things you want to learn about.