People who are in my squad can't..

[Huraka]

When I rescue a unit they won't come inside vehicles with me they only walk?

[kodabar]

You need to tell them to get inside vehicles. If you're already inside one, select the units by using their respective F keys (F2, F3, F4, etc) and you'll see them highlighted, then from the mousewheel menu, you'll find a command "Get in". If you're not in a vehicle, it's the same process, but you need to point at the vehicle before the command will show up in the mousewheel menu.

If you're in the driver's seat, they'll get in as passengers. If there are weapons mounted on the vehicle, they will man them. If you're in a passenger seat, one of them will drive and you can tell them where to go either by pointing and using the mousewheel or by using the map.

It takes a bit of getting used to, but you'll soon get the hang of it.

[Snuggly Overlord]

To add on this, you can press ` (or what ever your one is set to) and this will select all units