system
A chat on 4chan
human
OP,

1. Whichever one you go down, find one that is liturgical and traditional, that encourages you / forces you to fast, get in shape, and have a daily discipline. 

For Christianity, I recommend Traditional Catholicism, Eastern Orthodoxy, or Oriental Orthodoxy.

For Buddhism, I recommend traditional Zen. Avoid contemporary Buddhism and avoid Pure Land Buddhism. 

2. 

What's 'best' is tricky, because there's so much levels of ways in which one is better than the other that it gets tricky.
gpt
Ultimately, the goal of both religions is to dig deep into yourself, purging all of the ways in which you have devolved into animalistic and selfish behavior, detaching yourself from sensuality, and uncovering who you really are as permanently connected to the ultimate reality that underpins all of things.

These religions will use different formulas, ideas, concepts, and practices to explain and achieve these things, but pragmatically they function the same and are trying to achieve similar things.

'God' is completely beyond the limits of your intellect and only even somewhat interpretable through experience of 'God', and both religions are trying to use formulas and practices to gain that experience, but they functionally are describing the same thing.

As an example, Christianity is inherently dualistic - Christianity holds that there is a God who underpins all of reality by direct sustenance of the universe; God is constantly acting and permanently connected to all things. Buddhism holds that 'God' (Sunyata) is ultimately the real nature, and the dualism is an illusion. 

But Christianity makes it clear that all things are permanently connected to God and can't be severed from God, and that all things are infinitely coming from God; moreover, God is permanently inscribed into all of reality.

Buddhism also doesn't deny that the 'dualism' doesn't matter or isn't real. Sure, you may have a 'non-self', but that doesn't mean that your 'self' doesn't matter, or that your perception of your 'self' isn't real. In a sense, 'your' experience of the 'self' is very much real and distinct from Sunyata. 

I've drawn a picture, this is the phenomenon both religions are trying to describe using different formulas. Whether the 'thing' connecting us to God is a hard distinction but with us being entirely dependent on God's sustenance, or that 'thing' connecting us is not a hard distinction, doesn't really matter.
human
I've taken to calling God the 'Source'. It is the wellspring of creation, and the law upon which all is built. You can get into some repetitive mathematics when you get autistic enough, but God is still there waiting for you to look up.
gpt
>to look up

God is above and within