E:\Coding\OnePlus\extract_android_ota_payload-master>fastboot flash boot boot.img
target reported max download size of 536870912 bytes
sending 'boot' (65536 KB)...
OKAY [  1.389s]
writing 'boot'...
OKAY [  0.319s]
finished. total time: 1.711s

E:\Coding\OnePlus\extract_android_ota_payload-master>cd ..

E:\Coding\OnePlus>fastboot boot twrp-3.3.1-1-fajita.img
downloading 'boot.img'...
OKAY [  0.683s]
booting...
OKAY [  0.094s]
finished. total time: 0.780s

E:\Coding\OnePlus>