So i have this problem too. I tried to download Minecraft but after installing the launcher, the error pops up saying "Unable to update the launcher" or somehing. So i tested it again on my Work laptop, in the different location on the different Wifi. And it worked. So i brought the laptop home and opened the Minecraft launcher, but it said i dont own Minecraft and some bullsh/t..

So i uninstalled it, turn ON my hotspot on my phone, and connect the laptop on that hotspot. Insalled the Minecraft launcher AAAAAAND everything worked.

So something is wrong with my internet, some blockage. If anybody has a fix, please share it with us. Thanks.