1970 Volkswagen Beetle Could the engine be frozen

Engine Performance problem
1970 Volkswagen Beetle 4 cyl Two Wheel Drive Manual

I have a 1970 VW Beetle, not sure of engine size, possibly a 1600cc. This is my first VW.
I consider myself a decent mechanic, trained by my dad who was certified, and in my opinion, an expert. I would usually ask him for advise but he passed away a few years ago.
So let me begin with the events leading up to the problem.
One afternoon, while taking off at stop sighn the engine died, it started back up but seemed kind of sluggish. I gave it more gas and while pulling out into the roadway it seemed like the brakes where stuck on, and the engine slowly died. Then, when I tried to restart it, all I hear is the starter click.
My question is this, Could the engine be frozen? And if so, can I fill the spark plug holes all the way with oil, and by using another vehicle, push it in reverse to free it?
One guy suggested filling the cylenders with bleach. I don't know about that?
Have any ideas that might work?
This is our only car and summer in Arizona is no time to be without!