The size of your inbox is controlled by your ISP or email company so contact them.
A better way is for your friend to use a service like
There are several others out there if you just try and google "email large files".
Surface Pro (2017) vs Surface Pro 4
Where HTML5 is headed next
MacBook Pro v Surface Pro 5
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.