So there are two parks in California for
Disneyland. The OG Disneyland and Disneyland California Adventure Park (DCA).
DCA was built in 2001, so all of the lines in that park are wheelchair accessible and you can remain in your chair in line. Not sure if there are lines with restrictions for ones you have to transfer to regular manual chairs for so hopefully someone can chime in there.
HOWEVER, OG Disneyland has a lot of ride lines that are NOT wheelchair accessible even for manual wheelchairs. A lot of these queues are OLD and predate the existence of ADA. A lot of Fantasyland rides, Jungle Cruise, and Splash Mountain (if still open) are a few that come to mind but there's more. For those rides you will need to speak to a cast member and get a wheelchair return time, because you'll usually have to enter through the exit or a separate entrance. These return times are completely separate from
DAS.
WoC and Fantasmic definitely have wheelchair accessible viewing. I'm pretty sure the fireworks do too. I don't know about the parade though so hopefully someone else can chime in.