It doesn't matter if you don't have a foundation to go to interior design school. As long as you are willing to learn and have the spirit of persistent efforts, it is a trivial matter to have a foundation. The interior design school begins with the hand-drawing course, and after the hand-drawing course, it begins to learn the professional theoretical knowledge of the interior design school, including interior design drawings and drawing recognition, design principles, hand-drawing and rendering performance techniques, decoration structure, decoration materials and construction technology, decoration equipment and engineering examples, budget quotation and bidding, etc. After the theoretical courses, interior design schools began to learn professional software courses, such as AutoCAD, 3dMAX, lightscape V-RAY, Photoshop and so on. , is to use the computer to draw indoor and outdoor renderings.
In view of your present situation, I suggest you find a formal school with quality assurance, such as the interior design school run by the Interior Design Training Center of the School of Mathematics and Science of Sun Yat-sen University, which meets your requirements. Its courses include a four-month skills training course, a half-year interior design seminar and a diploma course in distance education. In view of your present situation, I suggest you attend the half-year interior design seminar of interior design school. The teaching mode is half-day face-to-face teaching and half-day practical operation, which is mainly to cultivate students' practical operation ability and is highly targeted and practical.
Baidu searched for "Interior Design Training Center of School of Mathematics and Statistics, Sun Yat-sen University", and the first one was them.