i tried to send a transaction but there was no option for me to sign or broadcast and i think i know the reason. because the co-signers of the multisig wallet also need to be multisig wallets?
Correct. The co-signer will also need to create a copy of the "2-of-2" multisig, using the
xpub from the original multisig wallet, and their own seed. So, person 1 would create the multisig using "Seed1 + xpub2" and person 2 would create the multisig with "Seed2 + xpub1"
If the co-signer loads a partially signed multisig transaction into a "standard" wallet, they'll see "Transaction unrelated to your wallet" message like this:
However, if the co-signer creates a copy of the multi-sig using their seed and the xpub from other signer, then when they load the partially signed transaction, Electrum will then detect that the transaction belongs to the wallet and enable the co-signer to sign and broadcast the transaction: