Get a beach tent.
You will need shade.
You can find it online.
It comes in varying sizes.
Also get a wagon. To tote all your stuff. Instead of carrying it ALL on your shoulders.
Bring mats... to lay on.
Now... imagine you have to use the bathroom.
You will have to take both kids with you. Thus, leaving your beach stuff/gear all there. Then what? Who will watch it? Thefts at beaches are common.
Or imagine one of your kids takes off running! Away from you??? Then what? You can't just leave your other kid there, while you go running after the other kid.
I would if you can, take another person with you.
They don't have to be looking out for your kids.
Bring a friend of yours.
I have seen, here at our local beaches, kids just WANDERING around the beach, while the Parent is busy with the other kid. Not even knowing their other kid was roaming far away.
Kids the same age as your kids.
Dangerous situation.
It takes just a split second, for a kid to be swept up by a rogue wave, and stuck underwater. Or, grabbed. By someone else.
I was at the beach the other weekend with my family. A kid about 3 years old just joins in with us and my kids. Hmmmm... I ask him "where is your Mommy?" the kid does not answer, just continues to play with my kids.
I ask him again... the looks down the beach and points. Well, there are TONS of other kids and families on the beach too. Like a needle in a haystack.
FINALLY, the Dad wanders over... his family was FAR away from where we were. Didn't know his kid, with with us. Nor, in our vicinity.