You can create a supplier by going to Suppliers> Create a new Supplier.  You're then asked to enter your Supplier name and Supplier Code.  The code is to differentiate between your Suppliers, every supplier must have its own unique code.  Tally will populate this for you, but you can change it if you wish.  Then you will be brought to Contact Details screen.  Here you can enter the address for the supplier, email address, and other information, but entering these isn’t mandatory.  You can also amend all of these details in future by going to Suppliers > Selecting this Supplier.