Noah didn’t have two of each dinosaur species on the ark?
Read the Genesis Flood by Henry Morris, one of the best books you will ever read. Also The Genesis Record
By him.
Not if they were already extinct before the Flood.
Look at the size of the boat. The big ones didn't fit. The smaller ones fed the carnivores. And the swimming ones were killed by the change in salinity of the water.
No, I'm not a young earth creationist. So that's the best I can come up with. Alternative theory - smaller ones were around after Noah; see the descriptions in Job.
Think small reptiles.
Noah likely considered them the same kind as the larger ones.
Nearest thing we have to a dinosaur today are alligator/crocodiles and maybe Komodo dragons. I don’t want to meet them in the wild.