I am a waitress I have worked at my job for 7 months and got paid 900 dollars but I claimed 3296.91 worth of cash tips so I will get checks that are voided bc I claim them. Will I get that back on my tax return?
Your checks were "void" because your earnings (tips) exceeded the tax liability in those pay periods. Whether you will receive a refund of some or all of that money depends on your specific tax situation with regard to exemptions, deductions, etc.
Assuming you are single and your total income for the year was the approx. $4200 you mentioned above, I would suspect you would get a large portion refunded. (Things like social security, state taxes-if applicable, and any other money withheld would not be subject to refund, of course)