in some cases (transaction that have a change) it is also possible to use another solution to "accelerate" a transaction...without having to modify this first transaction already broadcasted.
this solution requires to spend "the change" (output coming back of the first transaction) in a new transaction by setting a higher fee.
in this way, by processing this second transaction, the first is also included in a block... and it is a solution that also works with wallets that have not implemented RBF (but of course as mentioned above you need some "change" from first transaction...)
Generally, CPFP isn't recommended for a few reasons.
Firstly, CPFP isn't a recognized standard that miners have to adopt. It is purely voluntary, unlike RBF where most of the nodes and miners will see the RBF flag and act accordingly. Thus, it is a method that is a hit or a miss, if a miner happens to adopt CPFP, then you'll get your transaction included and if they don't, then you have to wait a lot longer.
Secondly, the amount of fees that should be set is quite ambiguous, unlike RBF where you have the liberty of creating another transaction with a higher fee (and thereby superseding the first transaction), the miners can potentially require a higher fee for your CPFP transaction, after considering the total increase in the size.
Lastly, it is non-reversible as well. There is no way of removing your child transaction, even if the network fees were to dip and your first transaction happens to be confirmed without the need for CPFP. As such, I would consider CPFP as a last resort, if you don't have opt-in RBF for some reason or you cannot change your first transaction due to merchant limitations.