Stellar Development Foundation (SDF) does not offer staking in any manner. If you are getting an email about XLM staking, it is a scam and will take you to a fraudulent website where it will ask you to enter your secret key.
Once the phisher has hold of your secret key, he is full control of your funds. He can send your funds to a centralized cryptocurrency exchange like Binance or send those funds to any of his other Stellar address.
So, if you receive a phishing email about XLM staking, mark it as spam and forget about it. That said, there is a way to enjoy interest if you have XLM or USDC lying idle.
You can sell your XLM for yXLM which pays you interest on everyday basis. This can be done on Stellar DEX like Stellarterm and then visiting yXLM-XLM market. Just login using your existing Stellar account and trade your XLM for yXLM or convert yXLM to XLM if you want the native Stellar token.
There is no third party involved here and interest is paid out automatically on daily basis.
Similarly, you can convert USDC for yUSDC and BTC for yBTC, both of which offer higher interest rate than XLM.