We're not offended. Either you can afford an attorney or you can afford to lose the case.

That your father's accusations are false does not mean money spent on attorney fees would be "wasted". If you don't have a lawyer you may very well lose -- especially if your father does have one. (Having one does not guarantee you will win, but it will dramatically improve your chances and will give you a much better bargaining position.) Hiring a lawyer to defeat this lawsuit may be the one of the best ways you ever spend your money money.

You can handle it yourself, risk losing for not being able to handle to complexities of civil litigation, and then have a judgment against you, wasting even more money than you would have by hiring a competent attorney to assist you.

If they filed a lawsuit against you, you must file a responsive document within the proper time. This may be a motion or it may be an answer with affirmative defenses. In any event, do not ignore the lawsuit or you will automatically lose. You can go to the law library or consult with an attorney and see if you can figure out what should be done and then attempt to do it yourself and continue to work hard to figure out what has to be done as the lawsuit progresses.

"Waste your time on lawyers"? Interesting. You don't know what to do yourself, so you ask lawyers here to advise and train you for free? Good luck in your studies and reading at the law library. You will be held to the same standard in court as are lawyers, so expect to have difficulties dealing with formal discovery, pleadings, motions, evidence, objections, witness and document submission and presentation, etc.