Termini Rome & Paris Bercy Station Platforms

[Tintown]

We are a family of 3 with quite a bit of luggage and will be taking many trips, but in particular two main trips, on trains in Italy in September. The first one is from Venice S.Lucia to Rome Termini, and the second is the overnight train from Rome Termini to Paris Bercy. If anyone is familiar with these stations I would really appreciate your help with the following questions:

 

Are there any steps, stairs or escalators to negotiate:

1. At Venice S. Lucia when boarding the train for Rome?

2. In Rome when getting off the train from Venice S Lucia?

3. In Rome when boarding the overnight train for Paris Bercy?

4. In Paris when getting off the train from Rome?

 

We are not sure what levels the platforms are on, and wondered if these two trains departed and arrived from ground level, or underground. Any help you are able to provide would be much appreciated. Thank you.