Hi,
A base is any substance that neutralizes acid. It may or may not be soluble in water. Those bases which are soluble in water are called alkalis. They are soapy to touch, bitter and corrosive. Thus an alkali is a kind of base. For example NaOH, KOH etc.
Therefore it is said that all alkalis are bases but all bases are not alkalis.
Hope your doubts are clear now.. 😊
Cheers !! 👍
