1 sq ft at ⅛" takes about 10 fl oz of mixed epoxy (144 × 0.125 = 18 in³ ÷ 1.805). Most tabletop/bar epoxies self-level to about ⅛" per coat; going thicker risks overheating and sag at the edges.
Bare wood releases air as epoxy soaks in, causing bubbles in the flood coat. A thin scraped-on seal coat closes the pores. Plan on roughly 1/32" of coverage for it.