Well to be honest. I could answer your questions but you have an extremely basic knowledge of electrical and should not be doing anything that involves wiring alone. You really need to do more research or find someone to help in person.

Those tube lights you refer to require a ballast, can not normally be dimmed, and produce almost 0 heat, so if you expect to get any heat from those your going to be SOL.

If your making a larger enclosure I would use radian heat panels over anything else. a heat pad is only good for maybe under glass or a thin plastic tub. Not much else.

You'll need a larger timer, but you don't use a timer to run each light, you use a specific timer to run up to a certain amount of wattage,

You need to do more research, because you have basicly asked someone to walk you through the entire process of heating and lighting a cage, plenty of tutorials online. more than you could ever read.

Once you have a fair knowledge of what your doing, feel free to ask and I will do my best to help.