" It Vegamite the same thing?"
Absolutely not, and mentioning Marmite in the same breath is likely to provoke a fatwah!
In addition to spreading on toast, Marmite makes a wonderfully warming drink on a cold day, used to be standard fare on returning from school, or from an evening activity in the winter.
Teaspoon (or to taste) in a mug, top up with boiling water. Dip in fresh chunky bread while waiting for it to cool. Babies love it (the bread dip) though I doubt the salt is good for them.
It gets its name from the cooking pot shown on the label, which is actually known as a marmite.