Do we need to upload old passport as we are putting travel information for 10 years at travel history? - NO
Can we do medical exam before invitation? - you can, depends on the panel physician. Some panel physicians asks for the ITA to conduct an exam, but majority of them don’t, you need to ask. However, it’s recommended to do the medical exam last as the it only has 1 year validity. Your COPR expiry is tied to your medical expiry date. With expected longer than average processing times happening nowadays, better do it last just before you submit your application. So when you get your COPR, it will have a longer validity. Furthermore, if your medicals expire and you still haven’t got COPR, IRCC may ask you do your medicals again, so another expense for you.
Thanks in advance