The best thing for battery health will be using the battery optimization feature and leaving the device plugged in as much as possible to take advantage of bypass charging instead of repeatedly draining and charging the battery. It needs to have proper USB-PD for that to work well, so disabling fast charging would be at odds with the bypass charging feature.
The OS only displays how many cycles were made on the battery, is there a way to check the % health of the battery?
It estimates the capacity but it's not shown in the regular user interface as far as we know. You can check it via ADB shell via /sys/class/power_supply/battery/charge_full
but we don't recommend using ADB on a production device. We could potentially add the info to the Settings app.