That'll be tough. No guarantees in politics. Who knows what will happen in 2028? We might see Barack Obama Jr emerge from nowhere to become President. Sometimes you only have one shot and that's it.
We know there will be a Presidential election in 2028. If Trump elects to run in 2024 and wins, his VP has the inside track to get the 2028 nomination, especially if Trump endorses him/her.
If Trump loses, then DeSantis still has the best shot for 2028. He is up for re-election in 2022 for Governor. Assuming he gets re-elected in 2022 for four more years, DeSantis will still be in office in the event Trump loses in 2024 with him on the ticket. The bottom line is that DeSantis has nothing to lose and a lot to gain.
The Dems have bigger problems in 2024. President Harris will be a weak horse hated by many. Without the benefit of massive election fraud, she won’t make it regardless of whether Trump or DeSantis is the candidate. If the Dems lose the House in 2022, you can expect gridlock and lots of investigations into the Dems with a GOP controlled House.