Congrats on going back to school - that is a big step to take after twelve years!
The key to writing, especially for us "older students," is to get away from the keyboard! I find that it causes brainfreeze! Find a comfortable place to write, without distractions. This could be a recliner, or a dining table, or even outdoors! Use a real pen and paper!!! Give yourself plenty of time - never procrastinate on writing assignments!
Skipping research papers for now, but, let's say you have to write an essay on any topic of your choice. You decide to write about which dog is your favorite. You have had many dogs throughout your life. The basic essay has an introductory paragraph, which ends with the thesis sentence. "Although I have had seven dogs over the course of my life, Dakota is easily my favorite out of all of them." Now, you need to explain why. That will take up the rest of the essay. You need to show what makes her better than all the others. Not just in one way, but in several ways. That could take three or four paragraphs. Each of those paragraphs starts with a topic sentence, and you then add supporting sentences. For example, "Although all of my dogs showed a willingness to protect me, Dakota did a better job of it than any of the rest. Clyde snarled at a guy who threatened me after we were in a traffic accident, but cowered when the man swung a baseball bat at me. Squawker barked like crazy when people came to the front door, but let them in if they handed him treats. Dakota, on the other hand, guarded my sister-in-law's suspicious-looking boyfriend for three days: she would not let him take a single step unless I told her it was okay!" After two or three more paragraphs like this, you then have a final paragraph where you wrap everything up.
Most schools have writing labs where you can get help - don't hesitate to use them! Also, keep in mind that you are being graded on things like grammar, punctuation, and spelling, not just your ability to create an essay. Once you type it up on the computer, use spelling and grammar checking features in Word.
You can do this!!