ExtendableGrids can calculate these as matrices after converting the gmsh info to an ExtendableGrid.
With examples/gmsh.jl:
julia> g=gmsh_t5();
ulia> g[FaceNodes]
3×28843 Matrix{Int32}:
1423 1423 255 1423 256 255 … 967 1914 1914 967 1271 1271
256 255 256 1539 1412 1412 2386 886 967 929 1274 1274
255 1539 1539 256 255 1539 1914 967 929 886 2852 1295
julia> g[CellFaces]
4×13801 Matrix{Int32}:
1 5 8 11 14 17 20 23 25 28 … 28837 28840 28840 28842 28842
2 3 9 6 4 7 21 22 26 12 16232 19348 28841 28658 28843
3 6 10 12 15 18 15 19 27 27 28517 26964 17764 19088 28601
4 7 2 13 16 19 22 24 10 29 28839 28838 28839 27068 28662
If this is what you need…