How should I request receipt of my portion of what my recently deceased Uncle left to his nieces and nephews, so as to not lose my SSI, which is my on

My uncle left his 4 nieces and nephews some amount of money (total amounts not figured as of yet) in his Navy Federal Credit Union, as an IRA to be put as a “Survivors Support Grant” upon his death. I have lived on SSI for over a decade and am unable to work and do not know how to accept the payment or deposit without jeopardizing it. I have found that you can use the money to “spend down” on things that the beneficiary does need or want AND the items are accepted as approved items that they may actually need or that are deemed beneficial to all of them. I’m just not understanding it all.