The factory bulbs from BMW are already LED. If you’re looking for more power, there are plenty of auto part websites and stores that can sell you a brighter replacement.
There’s a range of prices for new LED high beams, from $45 per pair to $180 per pair. It all depends on what you’re looking for and what brand you trust.
Once you have the new headlights, you can either install them yourself or bring your car to a mechanic. If you bought the headlights at an auto body shop, there’s a chance an employee will install them right there, in-shop.