Fighting vs large group of enemies is pretty much doable. Alot of ppl write it above.
Summary,
just keep yourself on toes, try to keep them in front of you ( If they block eachother, even better, same if you fight vs armored foe who have archer support. You keep your foe between you and archer if you cant reach him).
Of course that equip make difference. If you have heavy plate armor and you are fighting vs light armored foe, you can play more agressive, attack first and try to take them quickly out (Some combos for long sword can go through block pretty nicely if you manage to pull it), but still keep them in front of you!
Let’s turn the difficulty up a notch, ok?
Fighting vs large group of Armored enemies with shield. Just… dont try it if you are really not sure about yourself. And if you do? KEEP THEM IN FRONT OF YOU! Keep pulling back and hope for riposte. I would not advice to play aggressively vs multiple enemies with shield, Try to riposte every time that ONE guy attacking you ( See what i did there? You know where is rest of your enemies? Yes, behind that one guy that is attacking you).
Now for fleeing… You have full inventory, heavy plate armor and you try to outrun bandit with light armor? best luck if you dont have high stamina. Try to run and jump across stuff (fences, small streams, etc…). Enemies can try to catch you for long time if you dont break their pov. Sometimes its better to try to run for some time and then just turn and try to quickly dispatch enemy that dont have stamina aswell.
Running away with alot of speed on your character should be doable nearly everytime.