Yes, you can cut scrolls with a square blade....lean it back a little so only the corner contacts the leather.
For stamping, rest the heel of your hand on the leather, or mount it to a backer board.
Yes, it takes a lot of practice.
Now that that's done.....
Welcome to Leatherworker.net, best site on the entire internet!
Suggestions for places to read/learn.....well, you're already here. You might also take a look at YouTube, and do a search for leather topics. Though the person in the video may not be doing exactly what you want to do, the tool techniques are pretty common, i.e. How to use a swivel knife.
Spend some time reading, look at some inspirational images, watch a few vids.....you'll have this down in no time. If you run into problems and need help, don't hesitate to ask.
Bathrooms are down the hall, break room is over there ------------------------------------------------->
grab a stool at the tooling bench and stay a while. Johanna will be by sometime in the morning with fresh coffee.