[Hi10 Plus] Ubuntu 20.04 Mate on Hi10Plus

Hi, very interesting and thanks for your work.
My hi10 plus came with Android 6 and I managed to change it to RemixOs and changed partition to 16Gb.

On my PC I have windows, Linux and RemixOs installed. The question is… Could we have here 3 SO or not?

I managed doing that by modifying Grub. But I think we don’t have Grub here… Have we?

Please, explain how to install Android (or remix) besides Linux.

Thanks in advance.