I wouldn't worry about that too much to be honest. Alot of the protect battery talk have gotten to the extreme and there are lots of false information going around.
The phone, as well as the battery already have systems in place to protect the battery. Keeping your phone on the charger will have no noticeable effect on your battery longevity because the device already manages that. You can't overcharge a battery, that's simply false. Your main problem would be extreme temperatures, mostly heat. If you use your device heavily while it's on the charger, the battery is under constant stress and generating heat as it will be charging while being depleted at the same time. Don't get sucked into the narrative being flogged around by individuals who don't fully understand how these things work.
Sure you can take the steps to try to preserve your battery if it makes you feel less worried, it's your device after all but try not to overthink it or you won't potentially enjoy your device as much as you should.
On a quick note, the option to restrict the charge to 85% was only put there to appease people who believed otherwise. It doesn't hurt to have the option and it helps appease people and caters to a wider audience.
Use your device normally and you will be fine.
