The way to determine the largest object you can turn it to check two critical dimensions in the lathes specifications.
One; maximum diameter over bed, which is the largest piece that will fit in the lathe.
Two; distance between centres, which is the longest piece that will fit.
Beware of working at or near these dimensions. Things will be rather “tight”, it could be difficult to work with your material so close to the tool rest for one thing.
My advice would be to purchase as large a lathe as you can afford and fit into your work space.
I am a metal worker, I make scale model steam engines. When I purchased my first lathe I bought the smallest machine possible to get the job done, it was under powered and difficult to fit my material into.
Within a couple months I found myself trading it in for a much larger machine.
I looked at the specs of the model you mention. They are; maximum length 250mm, max diameter 150mm,
So I would imagine that you should be able to easily work material that is 200mm long and 100mm in diameter.
When I was younger my father worked in wood and would occasionally play with his lathe. He would take me into the forest with him and we would search for “burls”, which are those knobbly bits of wood you sometimes see growing on the sides of tree trunks.
He would saw them off with a bow saw and leave them in a warm corner of his shop to dry.
Dad always had a few of them ready to turn. The most beautiful bowls used to come out of those bits of wood. The patterns in the grain would captivate me.
Good luck with whatever you choose to do. Just remember this hobby can become addictive. Allow yourself some room to grow when it comes to purchasing key pieces of equipment for your shop.