Well i think better to convince your dad to join in this forum and learn something in bitcoin so that he can expand his knowledge about bitcoin that we are using bitcoin not in illegal activities and tell him that there is some countries that has stores that accepting bitcoin as payment like in paris and brazil.. Maybe he will accept bitcoin as legit and trusted..

A very awkward situation for you,in a way he probably wants you well since you say that some bad guys abuse BTC in your country,so he probably does not want you to become one of them.

One way is to try to talk to him and try to convince him you're not doing anything wrong with BTC.Second way is to you continue to use BTC without him knowing about it if possible.If you have some good friend to use his PC for crypto stuff this would perhaps help,although from the perspective of privacy is not the best solution.

If none of that works, then you can do nothing but to stop to deal with BTC until you grow up and move up.

Old people don't tend to like change. And that is including your dad if you are older than 18.

If you're a teenager then you're going to have a fun time trying to explain this one.

Talk to him about how there is a ton of stuff beyond just illegal activities that Bitcoin can be used on, show him some of what you're earned or whatever else and show him what you're striving to get to. Show him the technology and get him to see what it is so he treats it less as an alien concept and gets acquainted with what it is you're doing.

try to convince him to use bitcoin as a currency and not only as a mean of payment, if you do this he will take more confidence with bitcoin and he will trust it more

Spoken from experience, I do not think there are much chances that a father will take advices regarding money from his teenage son.
You will probably have to wait a while, a decade or so, until he might be willing to consider your opinion as solid and found.
Of course you can try to persuade him with charts, facts and numbers, but I would be really surprised if he would listen to that.

find positive news articles.

alot of fiat lovers would trust bitcoin if they seen the government positive about it. where senators, ministers mention bitcoin positively

http://www.afr.com/technology/senate-committee-says-bitcoin-should-be-treated-as-a-regular-currency-20150731-gior3u
https://www.theguardian.com/us-news/2015/apr/10/rand-paul-bitcoin-presidential-campaign-donations

you could also search out local retailers that accept bitcoin.


then you can show him how many times FIAT has failed people
credit card hacks
pick pocketing
ransoms

thus showing bitcoin is a currency like anything else. its just not understood because its still early and has yet to grow
then give him about $10 of bitcoin and tell him not to use it. but instead hold it and check the valuation every few months.

when the price goes up ask him is it more then the 0.01% interest rate he would have got if he just had $10 in a bank account

I do believe you will be forced to sell part of your coins directly to your father account, because words wont make he understand bitcoin at all, besides the fact that all money is used for good and bad things, its something your father know, fiat is used for ilegal stuff, media made bitcoin as dark currencie, good luck.

Ask him why fiat is trustworthy and why is it used for illegal activities...