Hi I'm looking at buying a second hand custom made Cabrinha Paddle Board 9'0" x 30", I'm just looking for a board to use in a lagoon or light surf
i weight 65kg and I'm 180cm tall just wondering if this board sounds alright for what I want

That should be fine for your height and weight, though if you're a beginner it might be a bit tippy in the ocean to start with. Just persevere and you'll be fine. Start in the lake!