Additional boards


I have a link for adding the attiny boards and now I need to add the esp8266 boards. Do I add the new esp url after the tiny one, or do i just paste the new esp url over the tiny and the IDE will store both automatically?

You need to add it after, separated by a comma. Or you can click the icon next to the "Additional Boards Manager URLs" input box and add it on a new line. You need to leave the attiny URL otherwise the attiny boards will disappear from the Tools > Board menu.