My kitchen drains,seem to be running outside I guess from the overflow drain into the yard... can I use a drain cleaner or do I need a plumber ?

First things first.

Can you plunge the system?

Can you use a snake to find the clog?

Can you gat a maintenance person to look at the p-trap and clean-out first?

Then look for the plumber, this could be a small matter, or it could be a huge one, all depends on a few items like above.

KBC