A - These are tropical / pacific islands. They number in the thousands and vary in size greatly from a few hundreds yards square the largest that have landmasses akin to Ireland. They have sandy beaches, coral reefs, calm lagoon waters, fair bit of volcanic activity, and those large enough have interior mountains/jungles.
B - The southern portion of this continent has 2 large peninsulas that lead into mountains to the north. The western area is mountainous and highland jungles whereas the eastern area is more lowland jungle and bayou/swamp land.
(Realized I made too C areas....)
C southwest - The northern peninsula of the island shares the mountain range with southern peninsulas in "B", but transitions to dense forests and hills, with rolling hills, savanna, and light forests in the most northern portion. It has a C-shape to it with a large island in the middle of it (important the islands remains there)
, which is also primarily forest, but more lightly than the mainland.
C northeast - These areas are either lightly forested mountains/hills (orange) or large, craggy glacial mountains (light blue) more to the north.
D - The northern section of this continent is fairly mediterranean along - mix of forests and light forest/savanna - some river lands coming down from the mountains. Through the mountains, which are similar to the Rocky Mountains (closed passes in winter, rise above the tree line, etc), is a vast desert akin to the Sahara. It has some relief areas, oasis, and some rocky mountains, but is mostly brutal, open, unforgiving sand.
E - From west to east... Dense forests slowly grow more sparse into a more open plains area, which slowly transitions to badlands/desert similar to the American Southwest. It becomes a mountain range similar to the Rocky Mountains (closed passes in winter, rise above the tree line, etc). on the eastern side, dense forests that slowly transition to lighter forests/plains towards the east coast. South of the central mountains is open taiga/steppe leading to the southern ice expanses.
F - These densely forested islands with central mountains spines down each
G - This is a very large, open rolling plains and savanna, there are some forested areas throughout, and a sizeable badlands/desert on the east coast. The southern coast mountains culminate into very inhospitable mountains/glaciers on the coast edge.
H - The mountains in area G funnel water into the lower H areas and are hilly/mountainous jungles and have a more bayou area on the northern peninsula
I - Very mountainous, inhospitable, volcanic. Some ice/glaciers on the northern edge. Very dark, bleak and volcanic rock.
J - Large central taiga with western and eastern forests. East is more mountainous with one large range ( Appalachian styled) and a smaller range in the center of eastern peninsula
The north and south "poles" are both continental, like Antarctica, but more mountainous.