go to developer (found in settings) and look for the USB debugging mode and the USB0 option below it, make sure both is enabled. click that android version several tries until it enabled developer mode. after that go to setting and go to about.
once done let it boot and you get to the tvbox dashboard, all looks fine except wifi and remote doesnt work.
flash that firmware H3_R69 firmware using phonenix suite, you can follow this Espanyol speaking dude tutorial ( just replicate what he do on the video) Well anyway, just open up the box and if you see some marking about Q44_V4.0_xxxxxxx (the date where the board was printed, it can be around last year 2019 or 2020 this june) download the mega download on the link ( posted by wooow) which include 2 mega links, 1 is the firmware for H3_R69 from sunveill android tvbox and the another one is the actual download files containing the backup firmware for the fake MXQ 4k 5g that runs Allwinner H3 with fake 4GB ram (1gb Actual) and 64GB ROM (8GB actual) and also a archive containing twrp which is very essential restoring the backup. If you go to Developer Options and see running services, you will see the ram usage occupies the 3GB of it all from system alone, normally, this only consumes around 2GB on free). I actually looking for the same firmware, mine is also comes with fake RAM and storage.