comments:
As your first leather piece is chrome tan, you just need to start with limited amount of tools, materials - Cutting mat ( those are widely available), some knife (cheapest most versatile option is Stanley knife), Stitching chisels ( Amazon , Aliexpress would suggest 5mm size can go 4 if you wish ) John James Saddlers needles (Guide to needle size) ( they are widely available on amazon, Aliexpress link ), And then waxed thread which fits needle size ( Aliexpress ) Generally smaller leather goods = smaller chisel spacing, thinner thread, thinner leather, and the bigger the more it scales up ( not really true always but to give an idea) Your leather is chrome tanned so you don't need edge beveller yet really. Maybe you need an awl but, for first tries i don't think its needed now. Another things you might need are some metal ruler to cut straight line and compass to mark straight stitching line. If You have first project in mind i can adjust this to needs, but this is generally a good start on a budget.