LOS

[Cross]

Once you get somewhere, right click to check LOS/exposure; if exposed move or put down smoke.

You should be able to calculate if you can get to a hex as the cost of entering each hex is given.

I thought trees blocking LOS depended on the visibility. Low vis they always block higher vis can see through 1 or 2 hexes of trees. But if you mean elevation then...

You will get better at reading the map over time.