Not enough information given here to tell if the plum is even either of those two types - there are many other kinds grown or encountered wild which produce fruits of interest. Otherwise there are morphological distinctions between European and Japanese plums other than fruit characters.

If you want fruit, your trees need to crosspollinate with another apple/plum variety. It would be really helpful to know what variety you have, so you can find good partners for them.

If someone you know or a neighbor have a flowering tree (and they know the name of the variety), you could cut off a small branch, bring it home and pollinate your tree by hand with a small soft brush. If you get fruit, just plant that variety.

Flowering cut branches can be left in buckets of water to allow natural pollinators to do the work for you.

Thank you all for your wonderful information

I Know plum is Damson but Apple don't know (Bought from Lowes)

Thanks

and I am in Zone 7

Damson is typically considered at least partially self fertile but will definitely bear better crops with a pollination partner. It is a European plum so any other European plum should work - Stanley, any of the Gages, Seneca.

And your safest bet with an unknown apple cultivar is a crabapple with a coinciding bloom time. And make sure you have pollinating insects around - orchard mason bees, bumblebees, etc. Fruit tree bloom times are often too early for honeybees to be very active.

Thank you for the advise. Do you know where to find the scion wood for grafting. I can try grafting these.

Thanks

There are various mail order sources available online: https://www.google.com/search?client=opera&q=fruit+tree+scion+wood+for+sale&sourceid=opera&ie=UTF-8&oe=UTF-8

Or you can contact your county extension service for more local sources.

I have better luck grafting to a tree or rootstock that's rooted in the ground than grafting to a bare root rootstock.

I've bought rootstocks and apple scions from Fedco in Maine. They sell rootstocks. apple and plum scions and also trees. other choices are Trees of Antiquity, Maple Valley Orchards, Eve's Cidery, Queener Farm, and Summerland Varieties if you're in Canada.

Another possibility is to find an apple tree in your community blooming at the same time as your tree and ask the property owner to take a cutting. This may not be quite the appropriate time to graft; but I think it may work. And then you could try both methods.

The biggest problem with buying scions is they charge 4 to 5 times for shipping as the price of a scion. Another problem is that you get hooked on trying different varieties. You should graft all of the pieces of scions you have to ensure success. From an 8 to 12" scion you can easily graft 2 or 3 times.

Thank you for your expert advice. Really appreciate.

Thanks