This isn't something specific to PowerPoint. You use the same method that you would use to create this character just about anywhere else in Windows. If you need such characters often, it's best to select a keyboard (in the Control Panel - you don't need to change your physical keyboard) that makes it easy to write such characters. For example, "US-International". For an occasional use, you can use the CharMap application, search for the special character, and copy-and-paste it (from CharMap to PowerPoint in this case). Or you can memorize the character number, or write it down somewhere, and then use it in PowerPoint. In this case, it is Alt-0225.
Press Alt Gr and the a key to get á. Press the ` key and a to get à.
Insert on top menu, Symbol and scroll down to the O with an accent
there is no accent mark on the word formidable
The accent mark over this letter é is an acute accent. The accent mark over this letter è is a grave accent. The accent mark over this letter ê is a circumflex accent. The mark under this letter ç is a cedilla.
on a English keyboard it is alt gr
if = si (withOUT the accent mark) yes = Sí (with the accent mark)
No. Now, if you spell it out as "televisión", you do use an accent mark.
you need a french keyboard i think
If you are talking about an accent mark called the 'accute accent', then no. It does not.
The accent is normally omitted in English.
The accent in frequencia is on the i. If there is ever anything that ends in "-ia", the i has an accent mark.
There is an accent if you're saying yes.
The English word "arithmetic" carries no accent mark. The equivalent Spanish word 'aritmetica' has an accent over the 'e'.