# She said

"Rachel said"

# See

"Look" or "Listen" or "Pay attention to what I am about to tell you"

# there is my servant Bilhah ... I will have children by her

At that time, this was an acceptable way for a barren woman to have children that would legally belong to her. The full meaning of this may be made explicit.

# Go to her

This is a polite way of asking him to have sexual relations with her servant.

# on my knees

"for me"

# I will have children by her

"and in this way she will cause me to have children"