l am a beginner surfer( 1 year of surfing)
heigh 5'6''
weight 150

your surfboard is company is varying as you like but you have to take a surfboard around 6ft

7'4-7'10 if you want to go short but YOU have to decide what board would be best for you, how do you like it floaty ? not so floaty, fast? cruise? by surfing a year you should kind of have an idea on what board you want to ride.

5 years experience, and im 5'6 with you only difference is im 105 pounds. Id say about a 6'3 or 6'4 for you, only 2 and a half inches thick and pretty wide maybe 18 inches wide to 20

Get a used board, any kind, and have fun learning.

already surfing for a year? good, l will asume you can pop up and eveything fine.
So what kind of surfing do you want to do? Straight line, manuevers, airs, barrells, what?
It will largely depend on that and the waves you surf.
go to your local surf shop and ask them, they are going to be the ones to really dial you in to your area.

get a board around 5'10'' if you want go for the shortboard but it can be a lot different than a longboard the problem is you need to tell us what kind of board you're riding now. i'm assuming it is along board and they ride a bit diff. do not want you to get frustrated.