You only need to use one of the methods to apply once.
You can check the progress of your Absentee or Vote-by-Mail ballot (or check to see if you already requested one) by using the Track My Ballot feature on the Secretary of State's website. "Pending" means your application has been accepted and we have not yet mailed your ballot. If it is "Pending" there is no need to apply again. The "State Election" is the November 3rd general election; federal offices are on the ballot.
The last day to apply for a Vote-by-Mail Ballot for the General Election is Wednesday, October 28, 2020 5 p.m.
For more details about Vote by Mail see here