Graph theory is one of the most favorite courses that I had in my college life. The professor does a wondeful job in explaining Graph theory concepts and also makes sure that all the students from varying backgrounds like CSE, Economics, etc are kept at the same level. The class was discursive and the level waas streams Inspite of being a Mathematics course that requires proof writing, the grading is lenient on that. Mathematics majors are judged at a slightly higher level as they are assumed to already have a good grounding of proofs. The course is completely absolute and one has to score good marks in every graded component like the asignments, quizzes and examinations. In my opinion, the assignments and the exams are graded more leniently than the quizzes. The assignments are interesting and students are expected to put a good effort in them. They are non-trivial and can't be expected to be completed within a day or two. Personally, what helped me to secure a good grade was to attend every class and tutorial and do the book-back questions in Douglas West.
Linear Algebra is the most important course that you will have in your college semester. It forms the basics for many topics like Machine learning, Big Data Analytics, Physics courses, etc. All this makes it a must-do course. I won't persuade you to take this course in college but it can be done online as well in more depth. There are tons of wonderful courses online. Some of my favorites are: MIT linear algebrawhich is by far the best content that I have come across in this field. Other good shorter versions are: Khan Academy and 3Blue1Brown. For someone who is math-phobic, I recommend reading this excellent book: Manga Guide to Linear Algebra. In my opinion, the course was slightly advanced and the examinations were pretty challenging. All the questions were application-based problem solving questions. Practice questions daily from the prescribed book by Gilbert Strang. In my time, owing to the huge demand of this course, there were 2 batches of professors. One used to cover the linear algebra through its applications and other used to cover it using theory. If you have a chance, take the theoretical course. It is important to build theory from scratch and understand the math properly.
Dynamical Systems, inspite of its widespread popularity is not something I will recommend. The content is good but the rigour and learning is absolutely zero. It gives a good introduction and building block for a study in Chaos theory but neither the exams or the labs test you on that. We perfunctorily covered some equations in class but never had an opportunity to derive it further or understand it thoroughly. It is really easy to score and the examinations consist of some questions that repeat each year. If you have a really hectic semester, it will be helpful to do this as this is a pretty light course for the number of credits it is being offered for.
Calculus is one of the most important and fundamental courses for a Math major and also for someone who plans to do a minor in Math. It is also one of the first proof based courses for non-Math majors. The professor is well-versed and none of the classes would seem boring. Knowledge of Calculus is useful in many fields such as Computer Science, Mechanical Engineering, etc. The exams are realtively simple and it is important to attend every class and read the book prescribed. We followed Apostol. If you have no idea about proof-writing, it is good to go through this How to Prove it. The exams were not well-structured and the emphasis was to gain knowledge rather than marks.
Numerical Analysis is pretty similar to Calculus. There are some important techniques taught here like Error calculation, etc. It is a pretty light course. Paying attention in class is enough for getting a good grade.
Disclaimer: A lot of things might have changed till the time that you take the course. Take the advice here after weighing all the important facts in your mind.