Possible to book separate trips on the same travel day?

Hi Railers! :)

I’m in an urgent need to travel back home and all the flights and busses are super inconvenient for me - therefore I’ve decided to buy an Interrail ticket on short notice.

Here a question as I’m not familiar with the interface of the app.

1. I want to book my ticket to my hometown and it’s showing me the whole trip with a connection. I want to take the first connection with a train that departs earlier - is it possible to book tickets separately in the app or it must always be a complete trip?
2. To clarify I’m traveling from A to B and from B to final destination C
   The train A→B is the a train arriving at the connecting station at 20:30.
   The train B→C is the night train departing at 21.
   Notice: the train company informed travelers that there will be railworks on the first route and that delays are possible. In order to avoid those unnecessary delays I’m planning to take the earlier A→B train (it’s a fast train operating every 2 hours). Is that possible?
   That way I can avoid any delays for my connection if problems occur.
   I’m also traveling on a day with high demand, if a train gets delayed or cancelled - can I get a free ticket as a renumeration?
   
   Would appreciate any advice, my trip is happening tomorrow.
   Kind regards to everyone! :)