I filed my taxes online through H&R Block and I did not print them out to keep for my records. How can I find them on my computer. I haven't received my taxes yet because I made an error. So there is some information that I need to obtain off there because I also can't find my W2 forum. So how can I find them on my computer

Contact H&R Block. They should provide you copy of your tax return.
Or you can get transcripts of your return from IRS. This is free and if you have fax number, you can get same day.
You can also ask for copy of your return. It will take 60 days and you will pay $39.
Read Your U.S. Tax Return: Missing Forms W-2, 1099-Misc, 1099-Int, 1099-R