There's never a problem with having over-sized wire. What does the installation booklet specify for wiring: minimum gauge, number of wires, and breaker amperage?

The installation manual was really not alot of help. The plate on the range did state the Kw rating was about 3.8KW and recommended a 20 amp circuit. The wiring scheme for existing will work with 10/3. Should I bump my breaker from 50 amp to a 30 amp??

I would be concerned if the existing 50A breaker was serviced by 10 gauge wires, although I suppose that's a moot point. If it's 10 gauge wire, definitely reduce the breaker to 30A or less. If the device "recommends" a 20A circuit, then that's what you should do. The 10 gauge wires can service the 20A circuit without issue.

My bad the wire is 8/3 with a 50 amp circuit breaker. My last question is the appliance Kw rating chart had a different breakdown depending on what voltage either 240 or 208v not sure what my house has. I live in a newer house (97) in a newer sub in florida.... I am assuming its 240v????

208 is typical only in commercial/industrial 3-phase situations. What is the configuration of your main breakers, 2 or 3?

It's almost certain that you have 240V, single phase service, given your description of a house built in 1997. Use the higher KW ratings for the appliance (provided for the 240V service).

is the micro 220 or 120? if 120 do you have a dedicated circuit?

208v 2 phase is very uncommon in homes outside of older mixed commercial/residential areas except for highrise buildings with commercial style elevators.