upgrades

Can you use upgrades on story mode characters or only on pvp characters. If you can use it on storyline characters how please help?

By finding or buying them. If, for example, you want to use a Staff Head to gain more energy, you would use an Insightful Staff Head. If you find a staff that is not what you want to use, but has an Insightful Staff Head on it, you can Expert Salvage the staff head and apply it to your staff. When you identify an item with a mod you have never had before, you get a message saying that mod was 'unlocked'. This means that PvP characters now have access to that mod. You can only use that mod on a PvE character if you salvage it off of an item that has it.

Depends upon what sort of upgrades you mean. Runes and Insignias can go on your armor. Some are only usable by a particular class(es).

Weapons upgrades are also usable.

As Magma said, you have to find them (drops/chests) or buy them though.

weapon upgrades

Inscriptions

Runes

Insignia.