Couple Q's, oil and brakes

Just means u need an oil change or the person that changed it last forgot to reset it, any independent mechanic can change the oil, and parking brake probably needs to be adjusted

 

congrats and welcome!

'maintenance required message is just a reminder to do whatever is required in the maintenance schedule that came with your car.
it's different at almost every 5k interval. if you didn't get one, log in at toyota owners and you can get one there.
brake cable neds some slack taken out. kind of unusual at 53k, but maybe the prior owner was hard on it.

should be simple and inexpensive. any mechanic can change the oil, but you should check the level before leaving, and check it at every gas fill up.

when you actually need new brake pads, rotors and etc., you need any savvy mech who understands that hybrids are special, and they need to read the service manual if they have never done one.
it's pretty easy, but crucial that you disconnect the 12v, or not open the drivers door with the pads out.

all the best!

 

Re brake adjustment: if the brake handle pulls all the way up, then yes, there is excessive travel somewhere that needs to be adjusted out. But I would look first at the adjusters built into the rear brakes ... their job is to make sure that the brake shoes stay the proper distance from the drums even as the linings wear. If those get gummed up and aren't adjusting well (which is a thing that happens), then you will notice excessive travel with the handbrake handle.

There is, also, an adjustment available for the mechanical handbrake cable going slack, only that's hardly ever a thing that happens, so if you adjust it there, the chances are good you're just creating a misadjustment one place to compensate for a misadjustment someplace else.

 

The maintenance reminder trips 5000 miles from the last time it was reset. It does NOT trip every 5000 miles total (50,000, 55,000 etc) so if somebody did maintenance early or late, that explains why you’re seeing it trip at something other than a multiple of 5000.

 

You should find a Toyota hybrid specialist, and take your car there for everything.

The auto-adjusters for the rear brakes aren't working correctly, and at a minimum need to be adjusted. Properly adjusted rear brakes will make the brakes feel less "jumpy".