If i go through the website will it pull my information? Also, am I assuming April 15th will be the last day and if so would at that point they just take the money from somewhere else such as my bank account or paycheck?
Yes, use https://www.ftb.ca.gov/online/payment_choices.shtml to pay your California income tax liability.
If you use the California Franchise Tax Board's (FTB) website, you will enter your personal and payment information as requested (no information will be pulled from any other location).
To avoid interest and penalties, the last day to pay your tax liability in full is April 18, 2017.
Withdrawal of your funds will be based upon the bank account, credit card, amount and date (specified by you). Tax payment will not be taken from your paycheck.