Front cover, front main and oil pan leaks

My 2.7 Eco Boost was diagnosed with these problems at 80,000 miles. Is this normal wear and tear at 80,000? I read the design was originally metal to metal in oil pan. The repair was to install new pan, gasket, and sealant. I read that the original design did not have a gasket so why would a gasket be used in repair? I feel like I am being scammed to an oil pan replacement that was a design flaw. The oil pan leak was approximately 80% of the leak. The additional 20% of the leak is coming from a front cover and front main. I do not know what these are, or how they affect my vehicle. I was advised not repairing causes engine failure. Are they related to the oil pan leak? I could not afford to fix them at the time of the oil pan replacement. I had to choose between the oil pan at 80% and the front and main for the addition 20%. What could potentially happen if I cannot afford to get them serviced them immediately? Is this considered a critical repair?