What is the link between address and use of the UTXO? I state that I'm still a beginner. I need some clarification. I am using the Testnet. This is the information regarding the address I used to receive funds from a Faucet

 bitcoin-cli validateaddress 2N7MaihNErbNH8XTkuZWtJYPzMQAWMPVKHd
{
  "isvalid": true,
  "address": "2N7MaihNErbNH8XTkuZWtJYPzMQAWMPVKHd",
  "scriptPubKey": "a9149ac58ff47e27214b158b38da04bc8cbf72def14387",
  "isscript": true,
  "iswitness": false
}
bitcoin-cli decodescript a9149ac58ff47e27214b158b38da04bc8cbf72def14387
{
  "asm": "OP_HASH160 9ac58ff47e27214b158b38da04bc8cbf72def143 OP_EQUAL",
  "reqSigs": 1,
  "type": "scripthash",
  "addresses": [
    "2N7MaihNErbNH8XTkuZWtJYPzMQAWMPVKHd"
  ]
}



  What do data mean? I interpret that my address will receive UTXO
  blocked by P2SH type scripts, correct? "iswitness": false means that
  this address cannot use UTXO segWit?


On this address I received the following output as input:

{
      "value": 0.01944571,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_HASH160 9ac58ff47e27214b158b38da04bc8cbf72def143 OP_EQUAL",
        "hex": "a9149ac58ff47e27214b158b38da04bc8cbf72def14387",
        "reqSigs": 1,
        "type": "scripthash",
        "addresses": [
          "2N7MaihNErbNH8XTkuZWtJYPzMQAWMPVKHd"
        ]
      }


The blocked UTXO is as follows:

"txid": "a61389ff9af670770182198a984a4c1785625c60795bd57645ecc78765b23679",
    "vout": 1,
    "address": "2N7MaihNErbNH8XTkuZWtJYPzMQAWMPVKHd",
    "label": "",
    "redeemScript": "0014778daf651b21684b572644b47d551fce0ff71c74",
    "scriptPubKey": "a9149ac58ff47e27214b158b38da04bc8cbf72def14387",
    "amount": 0.01944571,
    "confirmations": 116,
    "spendable": true,
    "solvable": true,
    "desc": "sh(wpkh([7de694b7/0'/0'/7']032c27921f2d15e7eca768c0e8a8b1aeb863328c74d6c194d41dde2888d4b0e75b))#6z7uwusp",


"Sh (wpkh ())" describes a P2SH-P2WPKH output and the public key with which it is associated.


  The descriptor is telling us that the hash (sh) script incorporates
  wpkh (Witness - Public - Key - Hash) output. In simple words the
  RedeemScript should match the HASH of this public key, correct?


When I unlock and use this UTXO my input will generate a separate txinwitness field.

"scriptSig": {
        "asm": "0014778daf651b21684b572644b47d551fce0ff71c74",
        "hex": "160014778daf651b21684b572644b47d551fce0ff71c74"
      },
      "txinwitness": [
        "3044022034a07f088dd88396cd378912a4ed6a156701b075f0facbbae810677048c390e602205df07e13bf4d56feece791a1b5e4d94bec9c93aae14bb87a1b4c6c54ae9bf2f701",
        "032c27921f2d15e7eca768c0e8a8b1aeb863328c74d6c194d41dde2888d4b0e75b"
      ],
      "sequence": 4294967295


I can't understand the link between my address information ("iswitness": false) and the ways in which I received / spent the UTXO.
Because the address you are using is a P2SH-P2WPKH address as you mention (sh (wpkh ())), you get the output

&quot;isscript&quot;: true,
&quot;iswitness&quot;: false

It is talking only about the top level (P2SH), because it is a P2SH address, regardless of what the script &quot;inside&quot; it encodes. It doesn't &quot;see&quot; the underlying P2WPKH when you call validateaddress. The only time isscript and iswitness are both true, is for P2WSH addresses. You can view the code which creates this RPC isscript/iswitness output here.
When you spend it, you reveal the script inside the P2SH. Because it is a P2WPKH script, which is OP_0 &lt;keyhash&gt;, that script is then evaluated as such (using the key/signature data in the witness).