How do i increase vocal range?

Im an experienced singer, singing in a rock band. And for recording
harmonies l, id like to expand my options. I've experimented with
using vocal fry exercises and all the basic exercises for a while now
but see little difference, but my voice is getting stronger. Any tips
or exercises anyone would specifically recommend?

I refuse to push to get to the high notes, if you're singing correctly
it should be simple .Thanks for any help!