In today's age a tithe usually goes NOWHERE because it can not go there.
We can give to people. This is not the same as tithing. You can even give 10% if you want but that will not be following the old testament/covenant to give 10% to the specific people. If you want to follow the OT find the right Jewish Christians and the right storehouses and all those details, then maybe it will be possible. But as it is I know giving to the local church organization Pastor I have would not be tithing even if I gave 10% of my income.
Here are some obvious suggestions for what to do with money
1. You can give to organizations to help poor people wisely (not to the irresponsible poor but the responsible or trying to be responsible poor)
2. You can give to someone else to support them doing ministry either through preaching, discipleship, helping the poor, opposing abortion etc.
3. You can use your money to oppose abortion. This is the best use, shamelessly I have not donated much of anything to this cause. If Nazi's were around, the most urgent matter and practical matter as a christian (aside from directly teaching scripture for if someone survives execution but dies and goes to a lake of fire due to a sinful lifestyle the fruit of a persistent rejection of God....) would be to stop their slaughter of those who should not be slaughtered.
4. You can use your money to support your parents, widows, children or other relatives you are responsible for.
5. You can use money to support your own ministry done through yourself, this is what Paul did sometimes.
6. You should save some of it, so that you do not have to beg and be a burden on the Church system which helps you because of irresponsible over-giving when they could have helped someone truly in need.
7. You can spend it on your own food, rent and clothes so that you do not have to beg and be a burden on the Church system which helps you because of irresponsible over-giving when they could have helped someone truly in need.
It is sad that I have to mention 5, 6, and 7. But you are not ready to give until you have done 6 and 7. Too many times I have spent money bailing out someone unnamed who said they would be generous to poor people, just after I was generous to them and told them specifically to save money for their own bus pass, so they can get to work so they can stop borrowing money and or receiving free money from me. Eventually you have to tell them to learn responsibility and that you will not support them anymore and or make them give you collateral. [This is why it is often better to give directly to the salvation army, a group to help people overseas or to a Church organization then to a "poor" person directly although sometimes you should give to a poor person directly (usually only if it is done exactly one time and no more for that person.) I know my Pastor is much more responsible about how he helps poor people than I am so I find it better to trust my Church organization and to give to them if I want to help poor people.]
By the way if you do not know how much to give 10% might be a reasonable amount you will still have 90% left over to be responsible for yourself, but at the same time you are not giving some small amount to other people relative to your own income.
