Hello and welcome to Vogons.

Fitst, I must say that I am not an audio pro, but I have played with various pieces of higher audio equipment, including some interfaces.

If your intent is to record the Sound Canvas' output into wave files (possibly converting to other formats too) as transparently as possible, I would guess that a very simple "DAW" setup would suffice on the software side. Something like Audacity would probably be fine.

On the interface front, I can't speak for the Mackie one specifically (I use a MOTU M2 and sometimes a Terratec 6Fire USB), but for your use case, practically any decent (no glaring flaws) entry level interface would function well.

On the cable front, I suggest you not skimp on cables, while avoiding snake oil crap. A good set of shielded cables from Hosa or similar (whatever basic shielded stuff your local music store has). This should be below 20 US$. The shielding made an audible and measurable difference.

As for how to guides, I don't have any that spring to mind (I might have posted something previously in another thread a while back), but basically you would want to hook up the SC-55's line out to your interface's input and set up volume levels to maximize distortion free output on the SC-55 while adjusting gain on the interface to a high enough level to get a decent signal to noise ratio while avoiding clipping (distortion due to overdriving the input). There is more to it than that, but if you do not hit any unexpected issues, it can be as simple as that.

Oh, and do test listen with headphones as you will more easily pick up issues like noise).

Hope that helps and please do not assume that I am 100% accurate/relevant as I am not an audio pro.

I guess i just need to know now what kind of cables to get and whereabouts to plug them. Like do I need TRS or RCA? I’m still new to this kind of stuff and wanna make it as perfect as possible.

SC55mkii has both 3.5mm stereo socket on the front panel and left/right phono/RCA sockets on the rear.

I'd be using the RCA sockets, as they are at line level. The front jack is primarily for headphones.

Audacity will work absolutely fine.