Greetings @anthonyabboud,
I imagine what is happening is that your SD card once mounted belongs to the root user. Therefore read/write actions to this SD card can only be done by the root user or with root privileges. By the looks of it the user inside your container is the “torizon” user so it makes sense that you can’t read/write to the SD card.
Now to get around this you can change the ownership/permissions of the SD card after it’s mounted. There’s a couple of ways to do this though perhaps the most straightforward way is with a /etc/fstab entry. There’s a good example in this post here: Automatic mounting of sdcard on boot
You may need to adjust the line slightly to fit your needs/use-case, but the important part is the uid=1000,gid=1000 portion. This will change the uid/gid of the mounted drive to 1000, which so happens to match the uid/gid of the “torizon” user. Thereby effectively making the SD card and it’s contents owned by this user allowing for reads/writes.
Best Regards,
Jeremias