Walls should join automatically as they touch so you need to stretch the end of a wall with the end node until it touches the other wall or trim it with the adjust command (CTRL + - (CTRL and minus) is the default keyboard shortcut).
There are other methods that you might want to look up in the reference guide or have a look at some of the basic tutorials - links are in the HELP menu.
Otherwise post an image of you situation for a more detailed answer.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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