So helpful! I appreciate it.

When I speak Arabic peopel always ask if I'm Syrian. They say I speak slower and it sounds like a melody. It's funny because that is what people say abotu Colombian Spanish; I guess it's in my nature to talk like that.

Also, I was looking for the Saudi dialect too.

If you ever need help with English let me know. I'm sure I'll post soon. I look forward to your helpful answers.

Khaleeji
1- طبيعي - How is this used in sentences? I have a feeling it's used like the English word "really" with the meaning of "actually/" Does that make sense?
2- مرني - Does this mean "pass by
3- أركب- Ride/arrange? Like I wanna ride with you? Also, probably used in a sexual nature.
4- غير- I just don't get its 100 uses.
5- جاهز- ? lol

 1- we use the first one in different context, 

this is normal, هذا طبيعي

in between setneces like if ur sayin - that thing happened- and u go like- it was obvious that its gonna happen so we say طبيعي 

2- the second i think has only one meaning -pass by-

3- the third means get in the car or arragning the legos but in shadda اركّب الالعاب

and means sexually that ur doing somethin with someone, not only for gays, for all genders

4- the fourth has different context

she is so different  هي مره غير

that is so unique هالشي مره غير

the dish is so special الاكله مره غير

he changed! he is not the same تغيّر

she is changing for the baby تغيّر لولدها

5- the last one manily means are u ready?

or used as ; the food is not homemade الاكل جاهز من المطعم ماسويته بالبيت

the dress is from the store  الفستان جاهز ما فصلته عند الخياط

 if u have any further questions im here to help

Well , I couldn't put the whole comment in one comment here, it says I passed 2000 letter
Then  when I cut half of it and past it, the problem is when I past it the Bold effect was already gone, and I pressed Submit -_-
Yes I can't edit it haha ( they should allow editing for 1min after Submit it )
Or at least allow to remove it so I can write it again in a better way

It's better to learn Fusha first, because having the right words and right meaning will help you understand other dialects, and find out that they change it a bit or maybe much from the real meaning ...

Khaleeji

طبيعي - How is this used in sentences? I have a feeling it's used like the English word "really" with the meaning of "actually/" Does that make sense?
It's more closer to be "natural" and some people answering by using it which mean "It's a normal thing " I mean when they said طبيعي as an answer
( can also mean "obvious thing" )

مرني - Does this mean "pass by

Yes, or "Pick me up","visit me"

أركب- Ride/arrange? Like I wanna ride with you? Also, probably used in a sexual nature.
Yes, but that because people there use few normal words to hint about pervert things"usually gays use it", but well don't worry they mean it pervertly between friends or people they know only so if someone said أركب will be to ride a taxi or car or something like that

غير- I just don't get its 100 uses.
It means "different, or deffrent than something"  when its pronounce is "geer"
Also means "change" when its pronounce is "gayeer" (strong ي)

جاهز- ? lol
"ready" , "are you ready ? "

All these I'm answering as my knowledge with Saudian dialect, because I think it could change a bit in other Khaleeji dialects

Lebanese

طالع- I hear this used for exiting, like on the freeway, and going out, like ne6l3 shi 4.
Also "going to", or "getting up on something high"

شايف - I'm looking ?
شايف = "seeing" or "Do you see that " or "yes I can see that"
أنا شايف = I'm seeing

أني / عني - I feel like they both mean "about me," can someone distiguish the two?
أني = more like saying أنا which is "I'm"

عني = "about me" , can also mean "instead of me" like take something عني (to carry it instead of me)

مية بالمية - ? I forget
100%, exactly, so true

Tan - I mean when someone says sara7a vs sara7atan
That usually isn't letter just Tanween this thing I mean ً two small lines on/under last letter usually
صراحة become صراحةً ,
and sometimes it changes the sentince meaning depens on the word's Harakat َ ّ ْ ِ

Specially in words like when we describing something,we add Tan at end sometimes

جيب - bring?
Yes, also can be a "pocket"

La - also means "for," correct? la ily ? for me?
correct, but La sound is also can be use as "no" or maybe La2 but while saying it with speed it sound La
لاء مو إلي = La2 mo ily = No not mine

adding "meem" at teh beginning of a word, صاير and sar - do they all mean different forms of become?
I don't understand what you mean by Meem, if you mean ما this is deny things, like
صار = worked
ما صار = didn't work
صاير = it/he becomes .... (smart, fast, good... etc)
ما صاير = it/he not anymore ... (smart, fast, good... etc)

This is hard haha I mean trying to explaining a dialect to English
By the way, I'm Syrian not Lebanon so maybe I wrote something wrong