Hey, cactus. I wanted a GTP as my first snake when I was 18, too
But sadly, they need (and deserve) an owner with a little bit more experience and commitment to keep them happy and healthy! So something more hardy and cruisey would probably be better as your first snake, in my opinion.
Olives and bhps are a large snake - and I mean large. They need good space and heating, and, particularly with olives, you would have a snake that in 2 years, your then 9-year old probably couldn't handle the snake on his own without supervision because of the size. But I've heard they can have lovely temperaments.
All the woma owners will tell you they're fantastic! Mostly easy going, with quirky personalities. And a good size for your family, also.
Other good first snake options, I would say, are spotteds and stimpsons. They are hardy and don't grow so big, so they're great while you are getting on your feet as a herper. Coastals, bredlis, darwins, diamonds, jungles are probably the next step up, being that they are bigger in size, but also (generally) have nice temperaments.
That said, all snakes can, and mostly likely will bite at some stage.
I started with a stimmy, some blueys, and a bearded dragon for the first 8 years of owning reptiles - all easy animals. I've now got a bredli yearling who has taught me about managing snappy snakes
and I'm moving on to some gecko projects, and within the next 2 years, GTPs and olives. Stepping up means you find your feet as an owner of reptiles, and make less mistakes that effect the happiness or health of your animals. IMO.
Let us know what you decide, cheers