We all got older and reached an agreement- they don't push my buttons and I won't respond by shouting, equally I will treat them respectfully and they won't shout at me.
Some things that helped in the difficult years:
I would always tell them we were leaving at least 10 minutes ahead of when we needed to. This factored in time for the farting around meaning I didn't get so stressed.
It also meant that if we were swimming for example, I could usually give them an earlier warning, so when they asked for more time, I could be the fun mum by saying 10 more minutes. I would also offer a bribe incentive if they dressed quickly with no complaining as long as we were quick.
Negotiation was good, as was giving them a choice, so teeth or clothes first? The red cup or the green cup? Give them control of small decisions so they feel invested.
Apologise when you shout, try to model the behaviour you want from them, so when you fuck up, make it right.
Equally, there was the day I took ds2 to school in his pyjamas and made him dress in the car so the others wouldn't be late, or the day he walked to school in his socks with me carrying his shoes so his siblings wouldn't be late. Not my finest hours, but it didn't happen again.
I was a crap parent to small dc, luckily for me they are all forgiving.
We are not perfect, all just doing the best we can, don't beat yourself up about it. If you feel you need support then ask for it. When mine were small there were courses we could go on, maybe you could look at something like that if needed.