I carved these pipes

[Trichocereus Panza]

what tools did u use besides a knife? (i kno, dumb question but i need to know this shit lol)

I use a hand saw to cut the branch. You might use sandpaper after the knife if you want it to be smooth (brings out the grain of the wood more).

I use an electric drill with a long 1/4" drill bit or a little skinnier, use that with a vice to drill the hole through the stem. Then a smaller drill bit goes through where the bowl's gonna be, to meet the hole you already drilled inside (you have to be careful in lining it up). I use a sanding tool with small drillbits and stuff to carefully dig out the bowl.