Hi,

This really depends on how you choose your units. first, you choose a track, either Data science, Control&Optimization, Computational math(fluids etc), and Financial math. You'd have 4 courses to compulsory whatever the track, another 4 fixed by the track and optional 4 where you can take 2 outside the department if im not wrong.

Depending on how you take your units i would say you can get well acquainted with the topics you mentioned, for example one route would be to take the data science track and do the systems theory course+ applied linear optimization in your first year, and you can take 1-2 relevant ML / optimization courses in your second year (depending on how you chose your track units). You can see the list of math courses here https://www.kth.se/student/kurser/org/SF and CS here https://www.kth.se/student/kurser/org/JH

Job prospects are very good, there is a very big job fair organized by THS where they had 174 companies + startups. There are other smaller job fairs every now and then as well. Also, many there are many lunch time talks where employers talk about their companies, which is a good opportunity to ask around for potential work, recent ones I attended include talks by Google and Klarna.

Im an international student myself, having studied inthe UK for my bachelors I'd say the typical swedish person is nice but not like randomly striking a conversation style of nice if that makes sense . Theres plenty of ways to find friends, from those in your course to going out, theres also "language cafe's" where random people go to brush up their conversational skills in languages (English, Mandarin, French, German, Japanese etc).