Well if you are a good guitar player you should be able to play all kind of songs not just country :)

Same for an engineer.
Engineering is independent of the field of work....
For me it does not matter if i design an connection for an industry structure of a home structure or whatever
Codes might be a bit different but mechanics is the same

best regards
Klaus

For residential construction the primary material used is wood, with concrete foundations and the occasional steel beam/post here and there. I would recommend browsing through the American Wood Council website and downloading/reading whatever documents they have there to start. Spend time learning the terminology for the various wood framing elements (different types of studs, different species/grades of wood). A lot of residential design is also prescriptive, and it can be very cumbersome attempting to get things to calculate out (unreinforced foundation walls for example). Going through your prescriptive codes to know their limitations would go a long way. Try to drive by some residential construction sites as well at various stages of construction.

I think it would be a good idea to familiarize yourself with local building codes. Pick up an ASCE 7-10 and your state/IBC and read through them - at least those parts which you can without getting bored. Probably be good to brush up on masonry and wood design as well.

I was in the same position as you some 17 years ago.... My thoughts:
1) I attended one of the Wood Solution Fairs offered by the WPS or APA or such. It was valuable.
2a) I started studying for the SE exam and really focused on wood and masonry shear walls.... Which were the major gaps in my design knowledge.
2b) Obtain a good reference on wood and masonry if you don't have them. Breyer's book on wood. RMEH (or something newer) for masonry.
3) Attend some seminars or webinars on the subjects you've less experience with. These webinars are usually reasonably basic and are good places to start. If they are too complex then at least you will be able to write down concepts and vocabulary that you need to research on your own.