It asks to do a 'prisma deploy' but I have only installed graphql-cli which doesn't have prisma.

See the note on step 1 of that tutorial.

Yes a 'yarn prisma deploy' works. I had done a global install for graphql, which failed during deploy. So there is still something intuitively missing, has 'prisma' was not available in the global space.

You need to

npm install -g prisma

in order to globally access the Prisma CLI