There are a lot of good cycling computers on these pages. However if you’re looking for a bike gauge specific for your electric bicycle that measures amps, watts, volts, etc. & MPH, time, distance, etc. there are other sources than Amazon.
The only electric bicycle meter available at Amazon is The Cycle Analyst 2.2. It’s available in a newer version at Grin Tech for less money. Do a search for words such as “battery meter for electric bicycles” & you’ll find at least a 1/2 dozen others. Keep in mind an electric bike gauge or “digital dashboard” that combines the basic functions of a cycling computer with the specific functions of a DC electric meter will cost considerably more than many of the units advertised here. Making a list of the various functions you really want will go a long way in helping you to stay within your budget. Take a look at “My Picks Page” for reviews on some of these products.