what respect is a simple ammeter designed to measure electric current like an electric motor?

An ammeter is an instrument used to measure the electric current in a circuit. Electric currents are measured in amperes (A). The most common way to measure current in a circuit is insert an "ammeter" in series (in-line) with the circuit so that all electrons flowing through the circuit also have to go through the meter. Since the ammeter is placed in series with the circuit, it ideally drops no voltage as current goes through it. It acts very much like a piece of wire, with very little resistance from one test probe to the other.

1) The more turns of wire on the secondary winding has in relation to the primary winding, the larger the increase in EMF. Induction coils evolved from scientists' and inventors' efforts to get higher voltages from batteries. Since batteries produce direct current (DC) rather than alternating current (AC), induction coils relied upon vibrating electrical contacts that regularly interrupted the current in the primary to create the flux changes necessary for induction.

2) No, they are different. Magnetic flux (?m), is a measure of the amount of magnetic field passing through a given surface (such as a conducting coil). Magnetic fields are produced by electric currents, which can be macroscopic currents in wires, or microscopic currents associated with electrons in atomic orbits.