when you are just beginning you can use the analogy of water in pipes.
be aware there's other ways of thinking about it.
in fact the British used to say "Pressure" to describe what we now call voltage
and say "Valve" to describe what we call a vacuum tube.
in simplest terms:
electrons move.
when they move past a point , an electric current is said to be passing that point.
when approximately 6 X 10^18 per second pass a point, it is said that one ampere is passing that point.
they do not rocket by at speed of light. they drift by, slowly, in a disorderly column like water molecules in a river. imagine how wide is a tiny wire compared to size of an electron - you get the drift...
an electron is such a tiny amount of charge that we usually deal with them in larger quantities - 6E18 of them is called a coulomb, after a scientist.
just like 6E23 water molecules is a mole. (where'd that name come from?)
something must induce the electrons to move.
that something is called "Electro-Motive Force", abbreviated EMF and E for short.
that force can come from repulsion & attraction of like and unlike charges which is an electric field (ever feel the hair on your arm around static electricity on a dry winter day?);
or from a moving magnetic field as in a generator
or from a chemical reaction as in a battery.
how hard it pushes on the electron is a measure of intensity of the field that's pushing;
how much work it does on the electron is measured in energy.. ever hear of an electron volt? It's a mighty small unit so we deal instead in joules.
one joule per coulomb is one volt of "pressure",
so if one volt pushes one coulomb per second through something
there's one joule per second going somewhere
which is one watt.
sounds confusing at first.
but EE's have a big advantage over ME's - our units are all nicely defined, already metric and conversion constants included. we needn't worry about mass in slugs or velocity^2/2g in our flow equations.
so spend some time getting straightened out in your mind the fundamental units of:
charge(coulombs),
current(coulombs/second aka amps),
energy(joules, aka Newton-meters),
power(joules/sec, aka watts),
and EMF(joules/coulomb, aka volts)
lastly be aware that just like water in a river
the individual water molecules move slowly
but a sound wave can traverse the length of the river much faster.
it's a different phenomenon.
you'll get into that when you study AC.
this technique helps us 'average bears' bootstrap ourself up toward more rigorous thinking.
it's a start
now I'm ducking for kevlar.
)