Which Board Should I Get?

Sorry if you guys have seen this type of thread millions of times.
Hello there, I have just had 5 surf lessons and I'm completely hooked and now I'm looking for a board, I had been surfing the largest board they had which I think was a 8 foot board (Don't quote me on that.), but near the end of the week i was on the shorter board which I found was much better and easier for me as I could turn more which makes sense.
I have looked around and I have seen the magic carpet board which looks very nice but it is out of my price range, I have seen many people saying that the best type of board for a Beginner is a longboard but they have never specified what a Beginner is (is that first time in the water or can just stand up?) I can stand up quite easily and can stay standing up with quite a high level of success. I can sometimes catch a green wave if I'm lucky but i have mostly been surfing the white water but I would like to start paddling out back and getting the bigger waves but I'm a little bit scared, but that's another matter, I'm going to be having my other 5 lessons in august this year if that helps.
If any of you guys/girls can help me at all that would be great!
Also any tips on getting my deep water confidence up‽
P.S.
I'm about 5'6/7 11/12 stone, quite fit but nothing like an athlete.
Hello there, I have just had 5 surf lessons and I'm completely hooked and now I'm looking for a board, I had been surfing the largest board they had which I think was a 8 foot board (Don't quote me on that.), but near the end of the week i was on the shorter board which I found was much better and easier for me as I could turn more which makes sense.
I have looked around and I have seen the magic carpet board which looks very nice but it is out of my price range, I have seen many people saying that the best type of board for a Beginner is a longboard but they have never specified what a Beginner is (is that first time in the water or can just stand up?) I can stand up quite easily and can stay standing up with quite a high level of success. I can sometimes catch a green wave if I'm lucky but i have mostly been surfing the white water but I would like to start paddling out back and getting the bigger waves but I'm a little bit scared, but that's another matter, I'm going to be having my other 5 lessons in august this year if that helps.
If any of you guys/girls can help me at all that would be great!
Also any tips on getting my deep water confidence up‽
P.S.
I'm about 5'6/7 11/12 stone, quite fit but nothing like an athlete.