I'm going to go into detail about everything just in case there's some correlation between the problems that I'm having. Scroll down to the bottom for the TLDR if you need to.

I bought a 2012 Lexus ls460 about a year & a ½ ago and hadn't had a single problem with my car until I got my oil changed at Walmart about 4 months ago. I noticed about a week after I got the oil changed that it had a

It's a lot worse than this now, though.
small oil leak. It progressively got worse and I asked a friend that is a mechanic what I needed to do & he told me to replace the oil filter housing cap. So I drove to Autozone got a aftermarket metal oil filter housing cap to replace the cracked plastic OEM one & was going to take it back to his shop the next day so he could put it on.
The next day, I crank my car up & after it turned over, it immediately stalls out. When I went to crank it up again, it cranked right up, but you could hear that the engine was running roughly, the check engine light, & the trac off light came on. I tried to see if it would drive & make it up to the shop, but I was getting very little power from the engine when I pressed the gas & it wouldn't go faster than 15-20mph or come out of 1st gear. I checked the code and it was a P0101, so I took the MAF sensors out & tried to clean them with MAF sensor cleaner, but that didn't work so I ordered 2 new MAF sensors.
While I was waiting on the MAF sensors to come in the mail, I had my car towed to my friend's shop so that he could install the new oil filter housing cap while I waited on the new MAF sensors. He was really busy, so it took him about 2-3 days to get to my car, but when he did, he couldn't move it to work on it, because the battery was dead. When he tried to charge it, the charger said it was a bad battery which is really strange, because I just bought this battery from Sam's Club about 9-10 months ago & it never gave me any problems except for their was a lose connection at the terminals at one point & my car died a few times, but I tightened the connection after I realized what it was & hadn't had a problem with the battery since. Anyways, I went to my local Lexus dealership & bought a battery from them & took it up to the shop. He installed it & installed the new oil filter housing cap & filled my car up with oil, but it was still running poorly & stalling with a P0100/P0101 code.
I got the MAF sensors in the mail & took them up to the shop & replaced them. While we were replacing the MAF sensors, the connection that goes to the MAF sensor on the right side(driver side) was messed up & coming apart.(I'll attach a picture), but we carefully we were able to disconnect the old MAF sensor & replaced it with the new 1. Then we replaced the other MAF sensor. We cleared the code & the engine cranked right up and sounded great.
I drove home(about a 12mi/20min drive) and it drove perfectly. It was accelerating a lot better & the only thing that I noticed was that the speedometer seemed like it was saying that I was going about 5-10mph faster than I was. I may be wrong, but it just seemed like that at one point & my GPS app was saying I was going about 5mph less. Other than that, it drove very smoothly. I even stopped, turned off the car, & got gas and everything cranked right up with no problems. I get to my house & my gf needed to go to the grocery store about 4 hrs after I got back with the car & when she turned it on, the check engine light & trac off light came on. The engine was still running smoothly & I drove it around the block and noticed no issues. I checked the code & now it's giving me a P0171(Lean code on Bank 1) code.
I'm trying to figure out if that code could be due to the MAF sensor connector being damaged. Or I noticed that it looks like air is seeping out of one of the hoses that connects to the air filter, but it's on completely & I zip tied it tighter just for good measure. I also read that someone was having similar problems due to a loose terminal connection with the battery that was giving the same codes & problems and I know that I had that issue before & it would explain the reason why my battery went bad so quickly. Or if it meant the MAF sensors that I just bought were faulty, but it's only giving the code for bank 1 so wouldn't it give the code for both if they were faulty MAF sensors?

If anybody has experience with some of these same problems or might have some insights into what it is going on, that would be really helpful. Thanks.

TLDR: My car started having issues & gave a P0101 code so I ordered new MAF sensors. Then, a battery that I've had for less than a year died & when I tried to have it charged, the charger said it was a bad battery. I've only had problems with a lose connection to the terminal that I thought I fixed a while back, but I bought a new battery & replaced it, along with 2 new MAF sensors. It drove great at 1st, but a few hours later when I cranked the car, I got a check engine light with a P0171 code. One of the connections to the MAF sensor is damaged and I'm wondering if that could be the cause or if it could be the battery connection or something else. I've attached pictures to where the damaged connector.