Not a lot to see in belek itself, market and lots of lokkie shoops. Belek beaches are good. Most hotels are AI so not a touristy holiday town, good for chemists and fake gear
The sat market is quite good as you do not get the hard line hassle but just a bit of banter. My daughter is used to this market and was shocked when she went Bodrum market and hated it.
the best thing we found about belek is the temperature is still warm right upto december where as it cools down in other parts of turkey.
1 tip is to take a day trip to alanya great town with castle on sea front.
only about 30 mins bus ride from belek.