Hello. I see different platform like nexo, blockifi, etc... that can borrow you crypto or stablecoin. I'm here to ask if you have a strategy for example you borrow btc with an interest rate of 6% and then you use it on defi with 8% APR. Thanks for helpful. 
You posted this at the 18th, I looked at the price of Bitcoin at that time and it looks like that it is almost the price as it is right now. In general, this strategy is a high risk low reward strategy. Its a low reward since Bitcoin is at the top right now. At this moment, borrowing just to buy Bitcoin is very risky. Maybe you can do that in the bear market. Borrowing some fiat money just to buy the dip but that too is very risky. Just use your own money to invest into Bitcoin instead of having a loan. It will be a double problem to you if Bitcoin went down by the time you entered and at the same time, you will be thinking how will you pay the money you loaned.