Absolutely no one has asked me for my thought on whether you should tithe from your government relief checks, so I will give my opinion anyway!
For Christians, everything we have is a gift from the Lord. That includes not only the spiritual truths we cling to but also our possessions and our finances. So whenever we receive something new, or come into a windfall sum of money, we surrender that to the Lord, that it would be used for his glory. Start there.
For some of us, this surrender means we automatically give a portion to the gospel work of the church. If that is you, you have your answer.
Otherwise, when it comes to this recent payment to Americans, my answer would be to use the money for what it was intended to do, get you through. If you need to use it to pay bills, pay them. If you need it for groceries, buy them. If you don't need it for those things, pray about giving it away to those who do have need. The church might be included in that and as far as Reservoir Church is concerned we will actively work to ensure our community is provided for.
Seek the Lord, listen to what the Spirit is leading you to do, and act.