Add words starting with letter "F"

[Showndarya]

Create a folder for "F" and add words.

Refer Contribution.md for more details on how to contribute.

Comment here if you're are working on this issue to avoid conflicts. Add reference to this issue i.e Issue #58 in your pull request description.

[smokyabdulrahman]

on it

[Niweera]

Here to help. On it...

[goelrohan6]

@Showndarya #330

[pjra99]

Please assign /assign