Foreclosure in CA is non-judicial, thus each document must be recorded with the county clerk's office and you must receive a copy of each. Civil code statutes stipulate minimum time requirements, e.g. time from NOD to Notice of Trustee Sale must not be less than 60 days, Notice of Trustee Sale to actual sale date must not be less than 21 days.
First you will get the Notice Of Default (NOD), this is referred to as the pre-foreclosure stage. Typically, before things went haywire, NOD's were issued and recorded at the 90 day late mark.
60-90 days after the NOD, typically the lender would assign the trust deed to an service agent (trustee) with the capacity to sell. This trustee would in turn issue and record a Notice of Trustee's Sale which had to indicate a sale date of no less than 21 days from the date of the notice itself. A copy of this notice must be ailed to you AND posted on the property.
On the designated day and time, the property would be sold at the courthouse steps either to an investor or other third party or it would revert back to lender (still considered a sale).
Caveats: The above uses typical timelines. These no longer apply as who knows what lenders are doing these days. Lender may at their discretion postpone the date of the sale for any reason and any number of times provided the auctioneer receives said postponement prior to calling the property address aloud. Borrower may cure the default and stop the sale up to 72 hours prior to the date of the sale.
Evictions of homeowners:
As far as eviction, these can not proceed until the sale happens (foreclosure). Once it happens, you as the former homeowner may get served with a 3 day notice.
If you refuse to leave, new owner must file an Unlawful Detainer against you (eviction lawsuit), get you properly served, provide you with the statutory 30 days to respond, and assuming you don't respond it'll take approx. a week for new owner to get judgement.
Then judgement must be taken to Sheriff, who will visit you, give you 3 days to vacate before forcefully removing you.