I mentioned in the post that my grandmother was an old person and her thoughts would not match ours, and she didn't know about investing in real estate, bonds, or stocks. And please don't think his fund is illegal.
     These dollars are her hard work because she was a public school teacher. He kept his hard-earned funds this way because he didn't want to lose them. But in terms of money, he invested quite a lot of money, like in a in a cattle farm and in the agriculture sector. Because he lived in the village. Not only that, he used to leave all the money on the ground; he used to spend money on all the necessities. But yes, gold and silver were taken out very little. And some family members knew about this secret place of her. You will be surprised to see that grandmother has arranged the interior of her secret place so beautifully, which is really admirable.

But my mother was afraid to invest because she had learned about several scams and also had a negative perception of banks.
  But I thank you all for answering my questions very nicely and solving my problem. I told my mom about everyone's opinion. He realizes his mistake and agrees to invest his money instead of burying it in the ground like this. I really didn't know that much about the subject, so I loved burying the treasure under the ground like that.
  Actually, everything has positive and negative aspects. And as times have changed, so must we.
 Thank you all again.