On 5/23/2021, while driving my Optima on US94 in Indiana, I noticed a clicking sound. Uncertain if it was my car, or somerhing else, I turned off my media, and realized it was my car. I decided I would exit the next available exit, when I saw black smoke behind me. I realized I wouldn't make it the one mile to the exit, so I decided to pull off unto the shoulder of the highway. The instrumentation panel showed the coolant on normal, right in the middle of H and C. The Electrical Panel indicator was no longer in the middle as normal, which is right in the middle of H & L. Instead, it was berween the middle and Low. As I began to slow down, the panel showed a message of "Turn off Hybrid Now", then the red engine light appeared. I wasn't stopped yet, slowed to about 40 mph when I suddenly lost power. I coasted and brake to the shoulder, when I began to see smoke coming up from the hood. Mostly from the passenger side of the hood. I popped the hood of the car, then went out and opened the hood. I saw flames under the engine, more towards the passenger side of car. I grabbed my purse and ran to the field away from the car. The car burned up completely within about 5 to 8 minutes.