With only two channels to record into (unless you upgrade or add to your interface) your options are fairly limited.
That said, there is a ton of good advice out there on how to record the classic singer/songwriter set-up with two mics, not least this one from Neumann
https://youtu.be/1fZf---TGTI?si=K80RcLoRA9LWPUrc. The main challenge is balancing optimal mic placement with trying to minimise spill into the other mic, so most advice tends to coalesce around some combination of Fig 8 and hyper/supercardioid mics.
Personally, I think the vocal is
so important in these types of intimate, minimalist set-up that with a given mic locker you want to first settle on which of your available mics sounds best on your voice. With that done, it's then a question of choosing another mic from your locker for your guitar and experimenting with placement to achieve a nice balanced sound with the vocal.
A pair of OC818s would give you all sorts of interesting and productive array options but you don't have that, so I would probably start with whichever out of the LS-208 or OC818 you prefer on your vocals and stick the other one on guitar, keeping in mind that the OC818 gives you those useful variable polar patterns to help control spill.
All of this comes with the standard Gearspace caveat which is that you should be devoting at least as much of your energies and budget towards refining your room tone.