1, our school is like this. First, we publish the list of tutors and the corresponding topics, and then we go to the teacher first. Some teachers have certain requirements for their students. If you don't get what you like in the end, you can also find a teacher on the list to give you another topic you like, or be assigned by force. 2. Generally speaking, they are all related to majors, but copying and pasting things from other people's ready-made things should not be so subtle, otherwise the defense will be pitted, and the teacher will only ask in the paper what is your own thing? 3. Do you want to talk about how long it takes to write a paper or the whole process from contacting the teacher to the end of the final defense? I don't know what your major is. Some papers are purely theoretical, and some can be done in three days. Some papers need physical objects, with software or hardware achievements. This depends on the paper and the specific requirements of the teacher. We began to determine the topic when the senior year was about to have a holiday, and then finished our defense in early June, because we wanted to combine the thesis with the actual results. Finally, good luck.