iPhone SE (1st Gen) Forgot Passcode

[whiteowl4]

I have three iPhones (2 SE and 1 5s) running with same Apple ID. I forgot the passcode used in the SEs(common passcode) while iPhone 5s passcode was different and I remember it. After exhausting all the chances of entering passcode, I had to erase and reset one of the SE. Now, when I am setting up as a new phone, it is asking me to enter the passcode, I tried one more time but in vain. So, now I have the option to click forgot passcode and enter passcode used in 5s. Should I just go for this option or again do trial and error to hit the right passcode. Are there any specific number of chances here eg 10 chances or now I can try for unlimited number of times? Also, remember I still have to unlock my other iPhone SE which had the same passcode that I forgot so if I am able to get it right, I might just save the other SE from resetting and losing data.
Also, how can I recover data after resetting? Any softwares?

 

[whiteowl4]

The reset SE is asking for the old passcode. There is an option to click forgot passcode. After selecting this, it asks to enter passcode of any other device but 5S is not mentioned there even though it is running the same Apple ID and I know its passcode. (Further, I restored the backup of SE from mac to a spare phone i.e. 6s. Again, it asks passcode and the forgot passcode option doesn't give the option to enter 5s passcode, surprisingly). Finally, there is an option of forgot all passcodes, haven't clicked that yet. What will happen if i select that? Should I keep doing trial and error to get to the right old passcode. (In this case, how many chances do I have and if I don't hit the right one after multiple tries, will my icloud data get deleted or Apple ID get locked)? Right now, in 6s it says you can not use certain services if you don't enter old passcode, what does this mean?
If I restore 5s with the SE backup that I had taken in April, will it ask me the passcode of SE? Also, after restoring the backup can Apple ID be changed?
In case Apple deletes all my icloud data, if I restore from Mac backup will I get all data back in my phone eg notes?
Final question, is it mandatory to turn on icloud setting on each device individually, even though they are running same Apple ID?
I know this is a precarious situation for me and I have asked too many questions in a single post but any help would be highly appreciated.

 

[now i see it]

Just click “forgot all passwords”.
I don’t know what happens next - but that’s the situation you’re in and Apple is giving you an option.

iCloud data is safe even if you’ve forgotten all passcodes. Apple won’t erase it.