We're going to be in Miami Beach as we do to get there, there's some collective

You can take public transport MetroBus, it has a stop nearby. You can see the routes in the Miami Dade Transit tracker app

It is correct what Lorena says, it depends from where you go, you can move on the subway and get to the station that connects with the bus ... there you take the bus and it leaves you on the main avenue that you could walk walking through the murals and visiting the shops, until you reach Wynwood (3 blocks approx). Or you can use Uber or cabify. Visiting Wynwood and walking it is safe as there is an influx of tourists, however it is in a problem area and that the State has invested to improve the area. My recommendation is: do not leave more than 2 blocks from the Wynwood quadrant. I was there in August 2018 Good trip!