using a site to log into multiple websites and populating fields in one go.

Hi, A client of mine provides quotes for his customers and has to login and re-key information into multiple websites to secure these quotes.
Is it possible for me to have a function on my site that allows them to key in all the relevant info once, which then log’s into the multiple sites, and secure these quotes?

Im not technical at all, so would appreciate some advice as to whether this is possible.

Many thanks in advance.