How do I install optiboot on the newest arduino IDE?

Hello I tried to install optiboot5 on my newest version of arduino and I tried putting it in the hardware folder and nothing shows up in my boards nothing new anyway i must be installing it wrong
does anyone know how it is suppose to be installed ?

Point your "additional boards manager URLs" in the Arduino preferences at
and use the board manager...

ok i found where i enter the URL but it says enter comma separated list and it has the attiny boards ithere i do not want to loose those boards how would I go about do that ?

Separate the two urls with a comma. Mine currently has:,

ahhhh your awsome thanks

i have no idea what im doing wrong here i put a comma after the last url and had to retype the whole url for optiboot arduino wont let me copy and past I did it twice and still could not get the new boards to show up this stuff is stressfull