Luna tips for new player

Hi! I'm fairly new to Rivals and Luna Snow, I love supports in games, so I decided to download Rivals, formerly an Overwatch player (illegal, I know.).

How do I use the abilities? In which scenarios? I can't seem to get the hang of it.. Should I attack enemies from time to time or just healbot?

I want to get her to Lord as well, since.. why not ;D, does it take a lot of time?

Thanks!