As tempting as it may sound to take a loan (or use a credit card) to buy Bitcoin, I would strongly suggest against it. When you are investing in Bitcoin you, you are placing a bet that you can time its price correctly, i.e. guess the local top and sell before it. As easy as this may sound, many have failed miserably in this game. And if you fail, you might need to wait for about 3 years for your investment to become profitable again on the next market cycle. All this time you will have to pay the interest rate on your loan (or credit card). Could you afford it?

I explain this risk among other on a video I uploaded recently on my youtube channel: What is the best time to buy Bitcoin?

Besides this, I am against debt of any kind. I have been debt free since the day I was born and I strongly suggest everyone does the same. You and your father have been wise to never have a credit card in the past. There is no reason to break this good habit now...