I assume you are kidding but since you don’t have a lightning wallet, I’ll explain anyway.
“Sat” is short for “satoshi”, the creator of bitcoin. 1 sat is 1/100,000,000 of a bitcoin.
We refer to sats because it is far easier to say “I need 10,000 sats”, than to say “I need 0.0001 BTC”.
There is a scam coin called “SATS”, only use bitcoin.