...I mean, kind of OP, but you could either use the 'set gamemode' function, or, if you don't have that function in 2020.2, just run a command to set the player in creative mode, (/gamemode creative), wait 60 ticks, and then run a command to put them back in survival mode. (/gamemode survival), running the commands from the player. (I do something similar to have a key-triggered spectator mode that's handy for building.) But, uh, maybe consider the implications of this, could be very broken depending on how players use it.
...I mean, kind of OP, but you could either use the 'set gamemode' function, or, if you don't have that function in 2020.2, just run a command to set the player in creative mode, (/gamemode creative), wait 60 ticks, and then run a command to put them back in survival mode. (/gamemode survival), running the commands from the player. (I do something similar to have a key-triggered spectator mode that's handy for building.) But, uh, maybe consider the implications of this, could be very broken depending on how players use it.