Welcome! Just to confuse you more there are several classification systems, they don't all link hair properties with curl pattern. There are plenty of 2c fine haired wavies.

Are you sure you are low porosity if you are fine haired and been flat ironing (damaging)? The DIY porosity tests are not scientific, you are better off looking at the way your hair behaves, using common sense, maybe getting a hair analysis.
THE NATURAL HAVEN: Junk Science - Hair Porosity Tests / Float or Sink

Fine hair tends to do well with hydrolysed protein, this is also strengthening for damaged hair. Some fine wavies find conditioner only washing weighs them down and they prefer a super gentle sulphate free (ideally anionic surfactant free) shampoo.
2a-2c, medium texture, porous/ colour treated. Three years CG. Past bra strap length heading for waist.

CO-wash: Inecto coconut/ Elvive Volume Collagen
Treatments: Komaza Care Matani, coconut/ sweet almond/ fractionated coconut oils, Hairveda Sitrinillah
Leave in: Fructis Sleek & Shine (old), Gliss Ultimate Volume, various Elvive
Styler: Umberto Giannini jelly, Au Naturale styling gelee
Flour sack towel, pixie diffuse or air dry.
Experimenting with: benign neglect