Bitcoin derives its value from a number of things. Perhaps the most prominent way is its scarcity and its stock to flow ratio.
Stock to flow ratio is the quantity of an asset that is already out in circulation divided by the incoming stock being added. So, in the case of gold, the new gold mined out of the earth each year gets added to the existing stock. This is the same for Bitcoin as miners get rewarded with new Bitcoin for mining. The Bitcoin they are rewarded gets entered into circulation.
So far, Bitcoin's price has largely followed this exact trend. Many have priced Bitcoin into the future using this stock to flow ratio model.