Help with light and heat

[JawsMew]

I have a tort around 50-60 years old who has never had an indoor enclosure and never had any form of light or heat.
I would like to offer the old tort the space its always had from roaming the garden, but I would like to offer it the chance to retreat to a safe place which is warm and dry. I am knockin a small entrance into the brick work of our brand new garage and then inside building him a enclosure which I would like to have heat and light for him.
I have only had him since Thursday, I am a complete newbie but I have lost my heart to a beautiful creature who I want to have with me for many many years. So PLEASE help. What lights / heat do I need? How much would this set up cost and how much to run. I want to look after this elderly shelled friend The best I can but I am so confused with lights and heat its not making any sense