For chickpeas, Quantity does not have to be exact as size may vary. Use 2 x 14-15 ounce cans or 1 x 28-30 ounce can.
For garlic, You can use 4-5 cloves, grow up to a whole head of garlic or even two heads of garlic if you are a garlic lover! Roasting garlic softens the garlic flavor, reducing the pungency, so you’ll find you want more than a few cloves!