The tree is a Brazilian Cherry. The fruit is edible, very high in VitC but also usually very tart.
You have to wait until the fruit is so dark red it falls off into your hand before it is close to being ready to eat.
Some people make a nice jam from the ripe fruit but it takes a lot of sugar!
It has a single seed inside but don't suck the seed or it will be even more bitter!
Don't throw the fruit in the compost because every seed will germinate making them almost a weed.
Trees are hard to kill without the help of chemicals or a big excavator to dig them out roots and all.