The welcome committee on the edge of the biome is a bit denser than the normal spawns once you're inside. Once you pick those off, it will get easier. Try to pull them one at a time if you can, outside the biome and kill them. Once it is relatively safe, put down some campfires to keep the area a bit clearer. They don't need to stay lit.

Then while inside, use the hoe to make paths. Any water shallow enough to grow cattails will rise enough for a dry-ish pathway. You can also walk across those without losing your weapon, but the leeches can still get to you, so paths are better.

Use a mace for skellies and blobs. Atgeir works great on most draugr. Spin attack before they touch you and then skewer. (Don't mess with the elites.) Use the bow at a distance whenever possible.

Always have poison resist active and leave before it runs out until you know what you are doing. It does you no good after you have been poisoned. Also get out of there before nightfall.

Your number one goal in the beginning is to find the very rare yellow turnip flower. You can look for them in any swamp whether it has crypts or not.