Ever since updating to 1.14, I have had this issue; chunks don't load, however entities do, meaning I can see through terrain and find caves and mobs. I have deleted the options text file from my minecraft folder, as well as the shader settings, as I have previously used Optifine and a shaderpack, however didn't have this problem in snapshots.

It is kind of game breaking, when loading terrain as I move about, the chunks kind of flicker in and out of visibility, breaking a block will always update the terrain.