Oil leaking, signals not working, etc.

Every town is full of independent repair shops. Start by visiting a few of them. Someone at each shop will explain what they can do to diagnose and repair these problems. If one shop does not have anyone proficient in one specialty area, such as electrical diagnosis or automatic transmission diagnosis, they will be able to recommend the best place to go for those problems.

If you plan on doing some repairs yourself, the best place to start is by getting a paper copy of the manufacturer's service manual. You can usually find them on eBay at a reasonable cost. Next, here is a link to a pile of dandy articles:

https://www.2carpros.com/articles

Look at these to see if you think you can handle the repairs, but be aware these are representative and procedures will vary slightly or be totally different for other car models and years. You have us for a resource too, but remember that we cannot see, hear, or feel the symptoms, so you have to describe them with as much detail as possible. Including observations and clues, such as at what speed it happens, whether only when the engine is hot or cold, and anything you can do to make the problem stop or get worse will help.

Cylinder head gaskets leak oil only very rarely. A leaking valve cover gasket is much more common and is something a competent do-it-yourselfer can handle. Look for the highest place you see oil on the engine. Oil will blow upward on the front of the engine from natural air flow while driving, but other than that spray, oil always runs down from the leak. Oil usually collects around the top edge of the oil pan too, so many people incorrectly think the pan gasket is leaking. We will wash the area first, go for a test-drive, then search for where oil is starting to show up.

What leads you to believe new brake rotors are needed?

For the signal lights, what does "as they should" mean? We need specific symptoms to know where to start. Do the lights act the same on both sides of the car? Is the symptom the same whether the head lights are turned on or off? Do you have a test light or a digital voltmeter, and know how to use it?