Posts
Any bend sharper than the Corner threshold gets a corner post. Each gate gets its two gate posts, and its opening is taken off the fence length. Between these head posts, line posts are spread evenly, never wider than your maximum spacing: no odd short bay at the end. A Closed loop comes back to where it started.
Gates
Place a gate along the line: a Walk gate, a Driveway gate or your own width. Each gate has its own price. A gate can be moved or removed; two gates cannot overlap.
Concrete
Concrete is worked out hole by hole: the volume of the hole, from its depth and diameter, minus the post. It is then turned into bags of the size you buy. Line posts driven without concrete? Turn off Set line posts in concrete: only the end, corner and gate posts are set. Head posts (end, corner, gate) can have their own width and a deeper hole.
The method, with a worked example, is in the guide How much concrete per fence post.