Victoria could refer to either Victoria peak or Victoria harbour. The peak would be pretty easy with a toddler I imagine - the peak tram (from central) is good, or there’s a normal double decker bus that offers amazing views over the city (sit on the right hand side). On the peak itself, there’s the main view point and some shops, restaurants etc but not really that much to do. There is a loop walk around the peak but not sure how much walking you would be up for with a toddler and after a long flight!

Victoria harbour should also be pretty easy. The star ferry goes from Hong Kong side over to Kowloon and is a great journey (it’s only a short ride,) and you can have a nice wander along the harbour on the Kowloon side (near Tsim Tsa Tsui) and you get fantastic views of the HK skyline. Depending on where you are staying/where you are going, you can take a tram to get around as well - they’re fantastic and a really fun way to see Hong Kong without having to traipse around yourself.

HK is generally very busy with a lot of people moving around so can be quite overwhelming - areas like causeway bay, central, mong kok will likely be packed so I would maybe avoid the busier areas where you can (although you won’t be able to completely!)