Milk (breast or formula) should be continued until 1 year when they can start cows milk. So if to want to continue most feeds by breast you are looking at the 1 year mark (or longer if you prefer!)
As you know weaning is not advised until 6 months.
To begin weaning I would just do all Milk feeds as normal and then once a day offer baby a new food- I did purées so can’t comment on baby led. Maybe an hour before milk feed is due so they are peckish but not starving. For purees you could start with blitzed carrot, parsnip etc. There are also pouches you can buy. They advise doing a few days in a row of each new food so that if baby has adverse reaction you know what it is too.
Don’t expect baby to actually eat much at first, usually you have a few weeks of everything being spat out. That’s normal.
When they do start actually eating you might notice the milk before or after is less wanted, you might not.
Then just gradually start giving another meal a day- porridge with fruit purée for breakfast for example.
Then you can add the third meal if you want.
You’ll find that once they are taking a decent amount the feeds will just drop by them self, it’s not something you actually have to do, you’ll just notice baby isn’t hungry.
HTH. Just gone through this was DD (7.5 months) who has taken to food like mad and dropped from 7 milks to 3 in 5 weeks!!