일단 동명사, to 부정사, 접속사는 적절히 사용하신거 같고 몇가지 부자연스러운거만 고쳐 다시 써보면
I'm interested in designing layout, so I want to be a architecture designer.
I have thought it's interesting to design buildins, and I've enjoyed looking for the pictures of colorful buildings.
There are some plans that I have to make my future career come true.
4번째 문장 이상없습니다~
Also, I'm going to go to the university where I can major in architectural design.
After I graduate the university, I'm going to open my ~.
Though it won't be easy, ~