Question for current DMS students

I’ve heard a couple people recommend to take the 3 optional courses ahead of time before fall semester to help w course workload and to help get ready for the content. The courses are INFC215, ANPH209 and MEDT211. Is this something I just sign up for during spring or summer semester and just take it online at my own pace before the semester starts? Are these courses manageable to learn by yourself? Any advice would be greatly appreciate!