I will get myself register……^^
Thanks

also 졸리다 would be nice one for someone who dozes off

Anyway, ‘-여’ is for linking two actions or two things.

1. linking two actions according to the time they happened
서울역에 도착하여 나에게 전화를 해라.
Call me when you arrive at Seoul station.

열심히 공부하여 부모님을 기쁘게 해드리자.
Let’s make our parents happy by studying hard.
(Studying hard is first thing and then it makes parents happy, at the same time it can be the means or way of the second sentence)

2. the first action or state can be cause or reason of the second action or state

길이 복잡하여 조금 늦었어요.
The road was congested so I was a little late.

3. the first action is the purpose of the second sentence
윤호는 돈을 벌기 위해 취직을 했다.
Yunho got a job to make money.

There are more usage of this but these are the basics.
And I think your example fits into No. 1 and the second case.

‘-으며’ is used when you list more than 2 things or when something is being two things at the same time.

1. linking two equal actions or states, so they are interchangeable.
you can change it to ‘-고’
그녀는 예쁘며 착하다=그녀는 착하며 예쁘다=그녀는 예쁘고 착하다
She is pretty and good.

2. while one does one thing, one does another thing as well.
you do two actions at the same time or you are in two states at the same time.
You can change it to ‘-으면서’
졸며 텔레비전을 보았다.=졸면서 텔레비전을 보았다.
I was dozing off while I was watching TV.

그는 소설가이며 교수이다.
He is a novelist and a professor.

I always see “여” and “며” e.g. XX을 대표하여 편지를 드립니다. and ….부담하며 버틸 수 없다.
Could you help to explain the two?

Many thanks.