Why Bitcoin has value could be a challenging idea to some. Most people just assume that money has value, as they have never experienced a fiat currency implosion, like what has happened in Turkey, Argentina, and Venezuela. Any money has value because people are willing to accept it in exchange for good and services.
While money has traditionally been metal, either gold or silver, the West decided to stop using that system in 1971, and the modern fiat money era was born. The vast majority of people simply don't understand that money is just a number in a bank's computer, and that it can created at will in unlimited quantities.
Bitcoin is digital money, but it is limited in amount. Most of the Bitcoin that will ever exist already is in public hands, and it can't be created without mining it, which also keeps the system running.
At the base of anything of value is trust, and the expectation that its value will last into the future. It is harder for people trust fiat currency, and Bitcoin is one of the only alternatives that exists. As people lose faith in their fiat currency, it is very likely that more will turn to Bitcoin, and other cryptos as well.