[JohnTan]

Hi everyone,
I am new to quantum mechanics and have been learning about Bohr, Schrodinger etc. however, I can't quite get my head around the basic idea of electron energy levels. First of all, I thought hydrogen only had one electron orbital (1s), however, the Bohr model shows several..are these representing electron orbitals or something else?

[Borek]

There are many orbitals, but at a given moment electron occupies only one. It is a little bit like having a $1 note and many pockets - it can be in only one at the time.

[opti384]

Well quantum mechanics is complicated and difficult. For hydrogen there would be only 1s because there is only 1 electron (for a neutral hydrogen atom). However, the case is different for other atoms. That is why the Bohr model shows several others.

[cliverlong]

<< cut >>
First of all, I thought hydrogen only had one electron orbital (1s),
<< snip >>

That's your misunderstanding.
Go back to the books / sources where you think you read that.
Do they really say (something like)
A single hydrogen atom has multiple energy orbitals /levels.
The "lowest" electron energy level is labelled 1s. The single electron in an uncharged hydrogen atom can occupy no lower energy level than 1s. If an appropriate level of energy (as e.m. radiation) hits the atom and is absorbed by the electron it will "jump" to a higher energy level. The energy distance of the electron jump is exactly equal to the energy of the absorbed incoming e.m. photon. That energy difference or jump is what determines if the incoming energy is appropriate. The electron is said to be excited when it is in an energy level higher than 1s. So the single electron in an uncharged hydrogen atom can occupy any one of a large (infinite) number of energy levels. The difference between the energy levels / orbitals decreases until finally if the electron absorbs sufficient energy it can leave the influence of the hydrogen atom completely and the atom has become as H⁺ ion.

I like Borek's analogy - very familiar, very understadable. Do you see why it is relevant?