Question Installing Linux

[The Hero of Orlais]

I've been trying for some time to start to use Linux now, but the problem is that I can't seems to boot to the installation (I use flashdrive to install Elementary OS, I don't have dvd rom) there's no option for legacy boot in the bios (Acer Swift 3), but when I first time plug my flashdrive and restart it normally, it automatically boot to the flashdrive, but now, I can't seems to do that, any suggestions? thanks.

 

[Grobe]

Guess this is an Acer problem, not a Linux problem. Do you have any settings in bios to change between bios/efi ?

 

[The Hero of Orlais]

Guess this is an Acer problem, not a Linux problem. Do you have any settings in bios to change between bios/efi ?

nothing that I can see, no, there is a secure boot though, I've tried to disabled it, but boot from flashdrive is still not there

 

[The Hero of Orlais]

Guess this is an Acer problem, not a Linux problem. Do you have any settings in bios to change between bios/efi ?

Actually no, I'm sorry there is an option for the usb drive, its called linpus lite, when there's no flashdrive attach, the boot option is gone, but my new problem is that when I want to boot through that, it said error oem or something, it also occurs if I boot from my bootable dvd