You can add a message field to the menu. According to the help:
“Type +M(nn) to create a message constant field of length nn.
Note: You will be prompted for the message identifier and the
message file from which the first nn characters of test are to
Type a question mark (?) in the attribute position of the message
constant to look at or change the message identifier and the message
It’s not the most elegant way to do this, but it may work.
If you are moving to web pages, why not use something like CGIDEV2, RPGsp or WebSmart?