where i can buy that pet catch roll?

If you mean how to catch new pets. You buy food from the petshop to use on them in battle to catch them. There are also foods for getting uip their loyalty so just read the descriptions and you'll figure it out.

to catch a pet go to the pet merchant, buy the corresponding food, and place your mouse on top of the food, the first one is up to lvl 15 pets, then 25 and below so on. Make sure you place it on your quickslot then click it when the monster you want to catch has a yellow teddy beside it's name