https://www.youtube.com/watch?v=EjgnlIgvK_0

I don't know any japanese but when in doubt, youtube.

It seems correct to me.

Baba is "Grandma" in a rude way. You're supposed to say "obaa-san" to be polite. Most "offensive" words in Japanese have a very normal meaning, but in an impolite way (most of "insults" in anime just mean "you"...).

Anyway, good luck with your Japanese! The beginning is pretty fun and shouldn't be too complicated, so enjoy! (it will get a lot harder if your objective is a high level though)

The first one is more like "Good afternoon" while the second one is "Good morning."  I'll also correct you here so you don't develop a bad habit.  "Ohayo" おはよう.  There's no "i" in it, even though it seems like it sometimes. 

As for the numbers thing, it's pretty simple if you just want to say your numbers.  However, be aware that if you want to say there's a certain number of things or people, the rule changes a bit.  Don't worry about it now since you wont get to it for a while.  

I would think that the chances are low that there isn't someone else like that here.  I will say that most of the stuff you learn in anime might not be very useful in Japan as a lot of characters speak in a very impolite manner.

Well firstly I thought how to count to 10 as I did not recognise a couple (in brackets what I learnt). Turns out I learnt it one way 20 years ago and there is another way lol. Guess out teachers did not care to tell us haha.

As for numbers, in your other reply where you typed out a sample you got it right

essentially it is   ->   X x 10s + 1s make up up to 11 to 99

The trick at learning numbers is really looking at the kanji

1 through 10 is simple enough: 一二三四五六七八九十

But once you hit the double digits, you need to look at the position tens/hundreds/etc.
11: 十一 (juu ichi)
22: 二十二 (ni juu ni)
33: 三十三 (san juu san)
96: 九十六 (kyuu juu roku)
etc.

If you know how to say the basic numbers in Japanese, then you generally would be able to say any number.
Just note that some numbers have multiple pronunciations, which can mess things up (4 = yon/shi, 7 = shichi/nana)

Kingdom Hearts is my favorite series so I'm an expert regarding the number 13 in Japanese.

13 = Juu san.

It's important to note that the numbers from 1 to 9 have 2 different pronunciations for different contexts. Usually when you're just counting up you can use the On versions of the numbers. In your case that would mean 4 = shi and 7 = shichi instead of their Kun versions yon and nana. The Kun versions are mostly used when you quantify something. For example listing things you would use yon instead of shi, but also futatsu instead of ni.

Though your version is fine too. I hope your teacher already told you that there are two versions.

Why not just search it up or ask someone who knows Japanese in your area?

Maybe learning by playing could help you. If you think so, try this: https://store.steampowered.com/app/438270/Learn_Japanese_To_Survive_Hiragana_Battle/ and the other 2 parts, which are about Kanji and Katakana, respectively