Qs about "finger guns" cantrip

this cantrip requires a hand and fingers to make a  certain gesture, but does not specify which hand to use.

1. So, can i cast it on my offhand and consider it as an offhand weapon?

2. this cantrip does not require concentration. Can i cast it both on my hands?

3. If i somehow have more than 2 hands, can i cast it on every hand which i can make a gesture?

 edit) can i cast a True strike cantrip with a finger guns? My hand obviously worths more than a few cp scraps, isnt it?

1. You can cast it on whichever hand you want. "Offhand weapon" isn't really a thing in D&D. If you're asking whether you can use it to make an extra attack as a bonus action, the answer is no, because it doesn't have the Light property.
2. I don't see why not; the spell doesn't say anything that would restrict this. But it would take two turns to do.
3. I don't see why not, though again it would take extra turns to do. There are playable species that have more than two hands (Thri-Kreen, for instance).
4. Probably not within the intent of True Strike, but ask your DM.

1. obviously this cantrip allows you disregard all the regular rules for casting spells - cast it as many times per round as you desire.

2. See above

3. Again, make the gesture as many times you want with each of your (however many) hands - why stop at just once per hand?

(edit) This is a hard no. True Strike requires a "weapon", finger guns are not listed on the weapon chart so they do not qualify. Also, fingers do not have a cost associated with them so they do not meet that criteria, either. Go to a bakery and buy some ladyfingers, and you might have a leg to stand on.

(This entire response is heavily laced with irony and sarcasm, and is not to be taken seriously)

If the original post was not intended as satire, I apologize for reading it that way.

As with most third party content, your best bet is to contact the creator and find out what they had in mind, since many of 3PP design is aimed at fun/"coolness"/whimsy first with coherent proofreading or playtesting being a very distant second. (This isn't to say WotC content is perfect either, but if nothing else they have Sturgeon's Law on their side due to a narrower release pipeline.)

With that out of the way:

1. What wagnarokkr said.
2. What wagnarokkr said, with the caveat that the answer to #1 means there  probably won't be much benefit to doing so.
3. What wagnarokkr said, but see #1 and #2.
4. While the owner of a particular pair of hands will likely see them as valuable, there is no mechanical cost assigned to them in the rules and therefore TS won't function.

Likewise, it's best to treat a spell as doing what it says it does verbatim unless the DM says something is allowed before you say something, not what it could do because you ask.

Because you otherwise would end up w/an unlimited supply of acid to sell via putting Acid Splash in bottles because of alleged ambiguity.

I pushed it once via using Thorn Whip as an emergency rope to get a player out of a pit trap Indiana Jones-style, at the cost of some piercing damage, despite that being logical to the DM & I.

That wouldn't be permitted at the median table.

I seem to have parsed the "more than one hand" comment differently to the others. I don't have access to the source, and wording matters, but typically, you can't cast a Cantrip more times if you have more hands available.