Hi there. No, REITs are not considered stocks. They are two separate asset classes. REITs are trusts, structured in a way where they are forced to pay out a particular portion of their profits, often in excess of 90%, back to shareholders. For this, they get different tax treatment than a public corporation. Stocks, on the other hand, don't have the obligation to pay back anything to its owners. Diviends can be cut, dividend policies changed etc.
Where they are similar however is in the ownership element of things. When you buy a stock, you own a portion of that company's assets, earnings etc. With a REIT, you own a portion of its earnings and assets.