How to improve Powerpoint and Excel skills - and the correct hardware devices to use for IB fresher

Hello guys,

I recently joined as an investment banking analyst and would appreciate if you can answer the following queries - 

1. I am currently using the HP Envy laptop with a Logitech MX Master 3 wireless mouse. The keyboard does not have a separate number pad but i seem to be comfortable with it. Should i continue with it or use a separate keyboard for speed.

2. PowerPoint - although I am able to get the desired slides in a PPT, it takes me too much time sometimes. How do i increase my speed. Especially in minor formatting changes 

3. Excel - how can I become a pro at excel. Any list of functions and formulas I should know which can help me? I seem to know most of the basic formulas and functions but seem to face some issues with advanced pivots 

4. Extras - anything else I could do to improve my productivity and reduce my time? Anything to manage Outlook and the files would be really appreciated.