Politically speaking, there is a clear-cut answer for what a good person is, I think. Someone who wants to improve the life of as many people as possible - even at the risk of decreasing their own circumstances. And that is usually what the left should aspire to be.

Socially speaking, this usually means to grant the same rights to everyone. Giving up privileges, overcoming the bias one might have against certain groups and stopping to exploit them.

Fiscally, this usually means supporting the poor. Conservative fiscal policies are mostly based on greed - 'conserving' the wealth of those who already have it at the cost of the poor. Going to your example, Germany, conservatives are all about taking money from the poor (Bürgergeld, Bafög, etc.) while denying any policies against the rich (just listen to the conservatives speeches during the vote of confidence: 'These so called super-rich people don't exist! We can't take from those! They are all family-owned businesses! Their wealth creates jobs!' [loosely translated summary of both Merz and Lindner] Which is just emotionally charged trickle down nonsense that has been disproven multiple times over.). The myth of 'fiscal responsibility' is also easily disproved if you look at Merz' policies he is campaigning on - they have been proven as nonsense within days if not hours.

It's easy to see which is morally the better choice, both if you're poor and if you're rich. Robin Hood isn't recognized as a heroic figure for nothing.