Getting a Ball python in september and in need of in-depth info about enclosure

[Markish_00]

First of all Hi everyone im new to the forum.

As written above i will eventually, after I get all I need for the enclosure and food for the animal, get a ball python. A normal one. I'm planning to get it in an expo near where I live, I'm Italian (specifying for climate overall info. I live in Parma, around Bologna. Pretty humid here)
-First question
Can I put the snake in a 70×30×30h cm (20gal) enclosure even if I get it as a baby? If I provide lots of small spaces inside is it going to be ok?
-Second question
How big should a heat-mat be in this enclosure?
(Planning to take a glass aquarium with slidable top)
-Third question
Do I need light bulbs? Infrared or just led? Can the light of my room be enough?

For now it's enough, I will get more question as we go, I just need multiple people to tell me different opinions, sorry if this thread will keep going for a while but I really need this to make sure lil ball python will be in great shape when I get him.(gonna be a male)
Thanks.