Quote from: rafik35 on Today at 04:18:01 PM

By doing CPFP did you meant that i should do it in my mycelium wallet or can i go elswhere with this? Is there any tutorial regarding this or this is strictly bound with wallet software?

It's not. The gist of CPFP is to make another transaction with a higher than proportionate fee to subsidize the "parent" transaction so that the total fee rates for both transaction would be reasonable. It is definitely not bounded by wallet software but doing it in the MyCelium could be simpler.

Quote from: rafik35 on Today at 04:18:01 PM

1. When i imported my wallet into electrum it shows 0 balance, but i see my tx's. Tried that with samourai, but balance was 0 with no history.

When importing BIP39 seed phrases, there are specific configuration for the addresses to be generated and can differ greatly between the wallets. IIRC, MyCelium uses BIP44[1] as the standard to generate the addresses. This is transparent to you and should no matter as long as you can do a CPFP within the wallet.

Quote from: rafik35 on Today at 04:18:01 PM

2. Mycelium says my balance is to low, which is strange if they allowed my to send tx with 44 cents and they say my leftover 4$ is too low. Support not responding isn't helpful in it that regard.

CPFP requires a high fee rate to compensate for the low fees of the parent transaction so that might be where your issue is. In this case, CPFP is not viable either unless you are able to send more funds into the wallet and spend both the change and the Bitcoins added. I don't think this is particularly feasible either.

Quote from: rafik35 on Today at 04:18:01 PM

3. Because of this brodcasting problem, i deleted (locally) the tx for it not to appear in my wallet, and balance went from 4 $ to 0. I read that it might appear again. Not sure if that's an issue for me regarding doing CPFP.

You can't really tell if it rebroadcasts or someone else rebroadcasts it for you until it reaches the mempool expiry of the nodes. I would advice you to continually check the Blockexplorers and once you get an error from searching the transaction ID, make a new transaction.

Quote from: rafik35 on Today at 04:18:01 PM

From theoretical stand point, if I would ask receiver to do CPFP is it possible to do it with any wallet? And if they do, miners are obligated to confirm my tx to because they both connected?
How can one spend btc they don't have yet? Or if the network see unconfirmed transaction it takes it into account?

Yes. CPFP works as the first transaction has to be confirmed for the miner to collect the fees from both of the transaction.

Unconfirmed transactions are still spendable, it is just that it cannot be confirmed until the transaction from which it is spending from gets a confirmation.

[1] https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki