Can I use corn flour instead of flour?
Simply so, can you use corn flour in place of plain flour?
No, in the large majority of cases you cannot substitute corn flour for plain flour (i.e., wheat flour) unless it's for a dish that says explicitly that you can do so.
Moreover, can I use cornflour instead of flour in a cake?
It suggests that using plain flour and baking powder and to substitute an amount of plain flour to replace it with cornflour would give a 'cake flour'. The combined flours should be sifted well before use. Cornflour just makes the cake crumb softer, is great for extra light sponge cakes like chiffon.
Corn flour is a type of flour that's milled from dried whole corn kernels. It contains the hull, germ, and endosperm of the corn and is considered a whole grain flour. Corn flour is usually yellow, but it can also be white or blue depending on the variety of corn it uses.