Tranposition Ciphers
Your second Answer first.
[2] write down the key column wise as shown ,then fill the plain text row by row so you will get the matrix of (len(plaintext)/7 x 7), now for ciphertext, take first row and then start taking the value in ascending order of key,  see below, key and particular row
for ex for
row 1:- {1:e, 2:r, 3:a,4:s, 5:b,6:l,7:e}
row 2:- {1:c,2:a, 3:m,4:s,5:n, 6:a,7:b} and so on..
so your cipher text would be erasb lecam snab.....
-Key:    6   3   4   1   2   5   7
-PT:      l   a   s   e   r   b   e
-PT:     a   m   s   c   a   n   b
[1] In columnar transposition cipher you read column wise, for ex. in  above example, you can write entire characters of column 1 then 2 ...
so cipher text would be ecdtmecae rauooleds ammernena ....