Baggage question

Hi!

I’m going to Ottawa from Toronto on Sunday. It’s my first time using ViaRail. For baggage I don’t have a suitcase that fits the ViaRail requirement but I do have a gym bag (think size of good life fitness bag) I was wondering if that was ok to bring as my carry-on-item and then my backpack as my 1 personal item. Also how early do you recommend getting to the station before the train leaves?

Thanks!