Congratulations on the first step you getting your new teeth. Your surgeon is absolutely right, you do not want to wear the Denture over the surgical and graft site for at least two weeks following surgery. The pressure from the denture can cause the graft material to not take and compromise the stability of the implants. Originally, implant placement protocol called for you not to wear the denture for 6 months of healing. With newer technology, implants, and graft materials, this healing period has been shortened. However, it depends on, and varies according to the procedure that was done, the number of implants, the extent of the graft, and the types of denture you are wearing. Do not put the denture in and starts chewing food without talking to your surgeon first. You can easily compromise the graft and implants and cause a failure of the whole procedure.
Please call your surgeon for more information. He/she wants the success of your treatment just as much as you do.
Best of luck