Hi and welcome.
If you look in the species specific section you will find a great caresheet on how to look after a sulcata which will tell you all about diet, temps, humidity, substrate and all other things you need to know.
How old/big is your tort?
If you post some pics of your enclosure with your tort in it then you will get more personalised answers to your question as to which type of bulb or tube suits your circumstances.
Do not use any coiled or cfl type bulb though because there is a high risk that they could damage your torts eyes so it would be a gamble.