Need some electrical help with my ‘68 Plymouth Valiant 100

if the oil looks like chocolate milk and or fills itself up (meaning, the dipstick shows at the add mark, then sometime later WITHOUT having added oil it shows at the full mark OR anywhere else above the add mark.) Rust on the dipstick.

are all indicators of coolant getting into the oil.

also white "smoke" out the tail pipe (not gray or black) indicates a lot of moisture in the exhaust system ( think what you get on a cold morning when you start any car up)
I’ll be on the look out for that, but I have a question; would it be better to get disc brakes on it? I’m just trying to figure out how to go about this new brake problem. I don’t exactly have the money to buy the entire disc brake set because pretty sure it’s like $1000. I guess it would just be better to repair the drums brakes?