I never say the 'f' word but I think it can have huge comedic value especially when someone says it in front of me and my children fall about laughing because someone said 'f***, in front of mum!'
Shouting "F**k off" is universally understood, I've found. When being harassed by a gang of young men in Turkey who were becoming increasingly intimidating, I shouted it very loudly. And they scarpered quickly!
If you don't like the F word, don't go and see the film "A Star is Born" because every other word is "F***". I really enjoyed the film and can tolerate the odd f* in context, and I know the film is about a rock star and we know that is how he might speak, but it was overdone.
Personally, I find that a well placed expletive is both effective and cathartic. If used too liberally, it becomes useless. So I like to save it for special occasions!