When you file a tax return, is it only federal income taxes that you can get back?

I don't know where you come up with $5000 but if you are a dependent and your income is $5800 or less, if you had any income tax withheld, in box # 2 on the W-2 you would file to get that refunded(a 1040EZ will do) if you are single and no dependents, your non taxable income is $9500, and the same applies as above if you are 25, you might be eligible for some EIC if this income you made is self employment income that is another matter but since you are asking about taxes withheld from your paycheck this would not apply

You can also get state back. These are the income taxes. Social security and medicare are payroll taxes and not refundable.

At age 18, you are most likely a dependent. If your W-2 is less than $5800, you won't owe, but all you would get back is the amount shown in box 2 of the W-2.

for a federal return, you get back federal. For state, state. FICA taxes are not refundable, and usually city taxes are not either.

Yes, that is correct. If you earned only $5,000 you should get 100% back, assuming you had some withheld.