RBF is sort of similar in the interface in that you have to right click on the transaction and select a higher fee. It will then make a replacement transaction that will bump the fee of the original one.
You don't have to do both rbf and cpfp. only one will suffice.
Also don't use old versions of electrum because they have bugs related to transaction fees that have since been fixed in the latest version so use the latest. Be sure to enable dynamic fees in preferences and set "Propose replace-by-fee" to "always".
hi, how to use " child pays for parent (CPFP) ", i dont see it in my electrum 2.8.1
Go to the history tab, find the unconfirmed transaction (tx), right click on it and choose "child pays for parent". Then in the window that appears move the slider to select a suitable fee and click on OK. Then in the next window click 'sign' and then 'broadcast'.
Alternatively you may have the option to do an RBF transaction. Right click on teh transaction in the history tab and click on "increase fee". Choose a suitable fee and click ok.
Make sure you select dynamic fees in preferences (tools menu > preferences) and set "Propose replace by fee" to "Always".