No, you can’t have two plecos in the same tank. Even though plecos are mostly peaceful and docile, they don’t tolerate their own kind. Plecos, especially male plecos, are territorial and aggressive towards each other. Keeping two plecos in the same tank will lead to fighting and even death.
Additionally, most pleco species grow to be very large, so for most tanks, keeping two plecos in the same tank is not feasible.
You should only house two plecos in the same tank when you want to breed them. But even then, they’ll need a 120-gallon tank or bigger. You will also need to separate them immediately afterward.
If you wish to provide companions for your plecos, try keeping them with these fish instead: