installing windows 2016 hp proliant

Sounds like you didn't include a UEFI bootstrap on the thumb drive and yo uve configured the server to default to boot via UEFI.  Gotta fix your bootable thumb drive.

You don't need to boot with installation media in HP Proliant servers. You can engage "Intelligent provisioning", so that the server will boot into Intelligent provisoning wizard and you can easily follow it. the video instructions are given below
https://www.youtube.com/watch?v=cL9NmoNIzdM

I already installed windows 2016 on it. just I need to set it to boot from it.

And I need to choose legacy boot every time it boots

Ahh, but see there's what I was getting at.

If you legacy boot the thumb drive, the installer detects the computer as a BIOS-based computer and the boot code it installs on the hard drive is legacy based.  And so the hard drive can *only* boot from legacy mode.

If you properly fix the USB thumb drive and boot from UEFI, then the windows installer detects a UEFI computer and lays down UEFI boot code on the hard drive and then the hard drive would boot via UEFI.

So if you don't want to change your boot settings to always be legacy, and don't want to manually boot legacy, then the only fix is to reinstall using media (CD, thumb drive, etc) properly created to boot on a UEFI computer.

But when I go through the Intelligent provisioning

it tells me that it doesnt support windows 2016

Check this out from HP official forum;
https://community.hpe.com/t5/ProLiant-Servers-Netservers/Intelligent-Provisioning-and-Windows-Server-2016-on-ProLiant/td-p/6929531

I ran the installation ,
and when it re-starts it doesn't boot I need to manually change it to legacy boot.

Do you know of a tool that installs all the drivers for the HP server (on windows 2016) ?

you need to download HP Proliant Service Pack. This includes all the Drivers and Firmware needed for proliant servers.
http://h17007.www1.hpe.com/us/en/enterprise/servers/products/service_pack/spp/index.aspx

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Accept: Cliff Galiher (https:#a42291135)

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