When it comes to upgrading weapons there are two types of experience items ~ mechanical and organic. Organic items don't give a lot of experience but they do grant your weapon an experience multiplier; mechanical items give you the most experience, so the most efficient way to do this is to use an organic item like a fang or a gel or whatever to get the x3 or x4 or whatever multiplier, then use a mechanical item like a bolt or a credit chip or whatever to get the most possible exp out of your mechanical items. I just woke up and that might not make any sense but hopefully it does~ Plethora of online guides you can find via google that can help with this.

Make sense now i just dk what to upgrade now lol im at chapter 7

Once again google is your friend, ultimately all the weapons lead to the same "final" weapon but the strength/magic/mods greatly differ so you'll want to ask yourself what role you want each character to fill~

I have but they all have diff weapons but what bout now on chapter 7 what weapons shoud i upgrade at this point the only ones i dis is lightnings gladius to
lvl2 and hopes hawkeye to lvl 4. Which with them i didn't know bout the ex thing so i have to do those sometime

anyone else wanna help?

no point unless u plan on doing all the sidequests cuz u can still blo through the final boss without ever upgrading

just want to know -.-
still looking for answers

Just google it dude~

just answer the questions or dont post in my thread dude~