Just to be clear, a newbie should not do it... You will have to install packet, and this will possibly (likely) break your OSMC install.
If you want to try anyway, you can start by trying with arora (a qt browser). For some reason, it is limited in size and is slow.
sudo apt-get install arora
arora -platform "linuxfb" -plugin EvdevMouse -plugin "EvdevKeyboard:grab=1" -