You can. First you need to enable command blocks in your server.properties file. Find the "enable-command-blocks" and set it to true. If it doesn't exist, you need to try to run a command block once in your server.
After that, if you don't already know, give yourself some command blocks using
/give <name> minecraft:command_block
Then put the command block and type in "/op @p" and put a button. This makes the person nearest to the command block get op if the button is pressed.
After that, if you don't already know, give yourself some command blocks using
Then put the command block and type in "/op @p" and put a button. This makes the person nearest to the command block get op if the button is pressed.
'Op' is one of the disabled commands for command blocks.
doesn't work
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