Get a Google phone number.  When you are logged in to your google number, text messages will come into your google phone account, no mobile phone required.  I set one up years ago, and Twitter decided to "limit my account" a few days ago, and making me accept a text message, so I used my Google phone today.  Entered the code, then they made me DO IT AGAIN! plus solve Captchas that were almost impossible to do.  Finally got back in to Twitter. I don't remember what I had to provide to Parler when I first joined, but now when I log in, it wants me to "add my phone", and I click "skip" each time.  So maybe in the beginning phone # wasn't required.