flashing jetson tx2 using host pc

hi, while working on jetson tx2 arm64 got removed from my board.
I tried to install ubuntu using bootable flash drive but nothing happened later on i decided to use pc as host and tried to install jetpack 3.3 in it i’ve successfully installed it in my host pc but unable to install it in jetson board. i also tried flashing using ./flash.sh jetson-tx2 mmcblk0p1 but it shows error flash.sh directory not found. Can you help me to figure out if to run flash.sh anything has to be downloaded, or anything else is to be done to start my jetson tx2 again. (the jetson board shuts every 5 sec. after showing message “reebooting in 5 sec…” and then restarts, this is running in loop.)