How much money, if any, am I expected to either give to the person or spend on him or her?

There is no expectation to financially support your mentee, either by giving him/her money or purchasing things on for him/her. Down the road, we hope to raise funds to have available for mentee’s needs. For now, it’s entirely up to you if you want to do nothing financially, or buy lunch occasionally, or something more substantial to help your mentee out.