Knocking sound + low compression + Very rough reverse

[Sivilaz 0]

So my Nissan Silvia has a ton of problems, and I'm worried my budget is going to go overboard. Basically, when I reversed the car it would turn off and it turns out 2 cylinders or whatever is not working and the spark plugs were completely messed up on 2 of them. They were very black and the one cylinder that worked, the spark plugs metal thing on the tip of it actually was broken off but still working. Anyways, replaced spark plug and batteries still the same issue it seems but I am not trying to reverse it.

When I turn on the car and let it run and even when it's warm it has a knocking like sound. Compression is low as mentioned first cylinder is 120, the second is 145, the third is 128, fourth is 145

And I noticed the oil is THICK as hell, I went to drain some and it took quite a long time, maybe this was so the sound of the knocking isn't so rough? And lastly, when trying to put the car into reverse it's a bit of a challenge as it has a bit of a problem going into reverse gear. Just looking at what the problems could be. Here is a video of the sound of the engine. Also the spark plug leads all seem to be fine.

silvia.mp3