Can i change normal weapon to int.

hello
i am totaly new to rf game
and i have some questions and i hope someone will answer me
1- can i change normal weapon to intense weapon?
2- in game i see ppl selling gems of diff tires but what i don't understand is that "what does the word set refeer to" does it refeer to 1 gem or all type of gems of same tire.
3-what is the use of upgrade slots in the weapon or item?
4-how can i instert talics in weapon and item?
5- whenever i go to crag mine field to mine some ores i get pked by diff race, so i was wondering should i go deep in the mining area so i can mine or their is any place near the portal were i can go their and mine?
6-i saw some ppl in crag summoning a tower , but somehow i can't evenbuy the light tower thing from the sunderries,i"i'm launcher" and i see em using this tower to kill the monsters and get the drop, any clue about that?
THANK U ALL

1. no
2. same class and 1 piece of each = set
3. how many times you can upgrade an item/armor.
4. by upgrading them along with gems.
5. if your playing 2.1.5 below,you can just simply mine beside of the crag port. except if your race wins,and you picked up your HMS(holy metal scanner something like that..)
6. you cant summon a tower if your not a machinist.