What is your nostr clients? If it is Amethyst you can set it with something like this "Down arrow" icon meaning is to set relay as "Read" relay while "Up arrow" is to set as "Write". You can set both active or just one arrow icon. Example: nos.lol - write and read nostr.wine - read wot.utxo.one - write and read nfrelay.app - read relay.damus.io write and etc.