MS Excel navigation

Personally, I fiond it much more productive to use the keyboad rather than needed to switch between mouse and keyboard, but some recent changes seem to limit my ability to do that:

1. In windows 10, I kept an arrow key depressed to continue moving.  Now I need to press it once for each cell movement.  Can this be changed?

2. Is there a way to use keyboard to move between excel tabs?  This was also on earlier versions