My line tool has gone weird when trying to draw straight lines. It is now drawing the line from a central point rather than end to end?
it’s normal. when drawing lines in layout you have 2 ways 
either you do small clicks and it’ll draw straight lines.
or you click and hold and it’ll draw bezier curves.
do small clicks, don’t press and hold, and you’ll be fine.
(this is a general recommendation, doing small clicks, even in sketchup, allows you to type stuff and go grab a coffee while working, holding your click will only bring you tendinitis in the long run)
I think this is a little more complicated. I am getting blue points to which the lines are joining themselves rather than to the object I am trying to snap to & sometimes it curves? How do I upload a screenshot to show you?
Screenshot of problem above
yes. this is exactly what I’m talking about.
it’s called Bézier curves. it’s a very standard way of drawing curves using vectors and tangents.
in Layout, they activate when you don’t simply do small clicks but when instead you click and hold.
top line, I did some small clicks, every click gives me a point, lines are straight from point to point.
bottom line, i did some click-hold, every click-hold gives me a point and a tangent, lines are curves from point to point that follow the tangents.
(the black circle means I’m currently pressing the left click button. see the difference between both.)
I appreciate your help. What if I don’t want my lines to go from point to point? I have always worked without them doing this? Is there a way of switching this off?
in Layout, it’s always been like that. or at least since 2018 I’d say.
in sketchup, if you keep pressing, you get only one line. if you do small clicks you get multiple lines.
in layout, in both cases, you’ll get many lines. that’s the standard way line tools work in all major vector drawing softwares.
if you want lines to stop appearing you need to press esc
I closed the file & re-opened and the issue has now gone away. The line was starting from a central point not end to end & I don’t know why. But thanks for trying to help