A premium game generally asks for payment to access the game, while a free-to-play game makes the initial download or entry available without that upfront purchase. Neither label alone describes every later charge or limitation.
What the distinction means
A premium release can have separately sold expansions. A free-to-play release can offer cosmetics, convenience items, currency or other purchases. The useful comparison is the complete route to the experience you want, not only the number beside the download button.
What to consider before playing
Check what is included, what remains optional and whether an ongoing subscription is involved. If you dislike recurring purchase decisions, look for a clear standalone offer. If you prefer trying before committing, inspect the free portion without assuming that every desirable feature is included. Compare actual editions rather than relying on a broad business-model label.
The useful takeaway
A premium game generally asks for payment to access the game, while a free-to-play game makes the initial download or entry available without that upfront purchase. Check what is included, what remains optional and whether an ongoing subscription is involved.