What have your read?
Flower rosin is mostly just a waste of flower. If you want it in carts you might go the “solventless distillate” route, but then you’d be looking for terpenes or hte.
You can absolutely make hash rosin by collecting trichomes from cured flower. With dry sift or bubble.
From there there are multiple ways to get to carts.
Wading through Search results for 'Rosin cart' - Future4200 would be the place to start…
Once you’ve read through a couple or six of those, you might consider EHO instead.
Hash rosin cart I was gifted in Canada last week.
Rumor has it this one was spun.