Are you plugged into power?
Did you first make sure there is no liight on the screen or caps key by holding down the power button several seconds? Work in a relatively dark room if needed. Don't work with sun glare on the machine.
Are you holding these shortcuts down before pushing the power button to start up and then through startup?
The correct key combination to completely wipe and reinstall the OS for 2012-2019 computers and reinstall the original OS is command-option-shift-R.
The correct combination to reinstall what already is on the a 2012-2019 machine is command-R. Command-R will not work if the drive is damaged that's internal to the computer or it was wiped.
It is adviced that you hook up a powered hub that has ethernet with your power adapter such as:
https://www.smklink.com/products/usb-c-multi-port-hub
https://www.siig.com/search/JU-DK0F11-S1
If your Mac does not have USB-C, a thunderbolt-2 ethernet adapter is available from Best Buy and others, like this one, for Macs with no ethernet and no USB-C:
https://www.bestbuy.com/site/apple-thunderbolt-to-gigabit-ethernet-adapter-white/5855333.p?skuId=5855333
This will ensure internet connectivity is there for internet restore. Some people have had difficulty using WiFi with internet restore.
Apple Silicon Macs, follow these directions
Use macOS Recovery on a Mac with Apple silicon - Apple Support