It's how it's given, not the amount

https://www.gotquestions.org/widows-mite.html

A billionaire gives millions to charities but may not saved, yet a poor person gives little and is.

So how fair is that ?

Millions given to charity yet the poor person is the one who spends eternity with Jesus.

Well, well, well, is that what they call religion ?

That's why true Christianity is not a religion.

Religious people believe or hope they can earn Salvation but true Christians believe that Salvation is an undeserved gift of grace that is freely given (cannot be earned ) to all who accept Christ as their Lord and Saviour and ask Him for help to resist sin.

Yes, we will continue to sin and often knowingly, yet our desire and want is not to, we confess alone to Christ of our wrongs and He will erase them as if they never happenned.
http://www.adevotion.org/archive/how-to-confess-your-sins-to-god

Works offering giving that we do with a heavy heart or reluctance might as well not be done at all for they will be burnt to ash at The judgement seat of Christ but yet the believer is still saved.
https://bible.org/article/doctrine-rewards-judgment-seat-bema-christ

The poor person who gives from the heart will receive eternal rewards, the rich person who gives because of their ego will receive nothing, but both are still saved since they have accepted Christ as their Lord and Saviour.