How do I give an item from my inventory to a follower? I want to give items from the crash site to Virgil to equip him.

As posted in the other thread:

1) Right click on their portrait and select Inventory.

2) Drag items from the right side of the screen (yours) to the left side (theirs).

3) If they are willing to use an item, it will autoequip.

To see what they have equipped (and to take it away if you want or need to) click the little human figure to the top left above their box, right below the big circle.

Followers generally decide one item is better than another if it's worth more gold. Doesn't matter if it's cursed, or too magic/tech for them; overall, if they can use it, they'll equip it. So if you're using a follower as a pack mule, only let him hold wrong-size armor, or give him a gun OR bullets (or a bow OR arrows) but not both at the same time.