So I just stumbled upon the wikipedia page for squaring the circle and learned that it's impossible to do with only a straightedge and compass.
Is this possible if we are allowed to use any other simple tools, or do we need something to do arbitrary calculations for us(like a calculator)?
I believe the extra tools we sometimes see discussed, as for trisecting arbitrary angles, are restricted to finding certain algebraic numbers, not transcendental, so no.
On the other hand, if we switch to the surface of a sphere, it is fairly easy to produce (some thought is needed ahead of time to do this by the rules) a circle around the North Pole and a "square" with the same area. A square will be bounded by four arcs of great circles, of the same length, with corner angles equal; these angles will be larger than $90^\circ.$
The limiting case of this is simply the equator itself, which is both a circle around the North Pole and a "square" with all four angles equal to $180^\circ$