Couldn’t tell you but it looks like a single speed with a steel frame made somewhere in China or the Far East. These are pushed out under the various names of the marketing companies in the U.K. or Europe. It’s not a conversion from a old bike.
You could try a fixed gear forum for a name or search the ads on
eBay for SS bikes. Yours appears to be quite well made and some thought has gone into it unlike many that are made to lowest denominator of quality and components.