here is an article about cannot and can not.
These two spellings [cannot/can not] are largely interchangeable, but by far the most common is “cannot” and you should probably use it except when you want to be emphatic: “No, you can not wash the dog in the Maytag.” AskOxford: Both cannot and can not are acceptable spellings, but the first is much more usual.
Technically, "membaca" and "baca" has the same meaning. "Baca" is base word for "membaca".
Membaca = prefix 'me' + 'baca'
When to use baca and membaca? 'Membaca' is the grammatically correct form of "to read". Therefore, it's used in written language and formal situation. 'Baca' (the base form) is commonly used in daily conversations/informally