How to focus gantt view for primary project when dealing with multiple teams?

[Bea Tea]

Project A is my engineering project team.

There are Epics, Stories, Tasks linked to other Project B and Project C dependencies (who have their own fix version and flows).

1. How can I focus the gantt/roadmap bars for Project A tickets?

- If I don't, the list of tickets will be very long.

2. How do I ensure all project dependencies are shown across Project A/B/C or other projects under the Dependency tab?

3. Will changes I make in the plan (drag and drop/rank, drag date bars) impact Project B and C issues? (I am not the owner for those teams)