Canadian students can apply for loans through their home province, for further information see https://www.csnpe-nslsc.canada.ca/en/home
If you require loan forms to be signed, please send them to the Student Funding and Fee Policy Team at StudentLoans@admin.cam.ac.uk. Clearly state where you wish the completed form to be sent (i.e. to you at your College, or directly to the relevant Canadian agency).