Advice for a nearly 20 week old baby

Hi guys my little man Neo is 20 weeks old on Monday and will turn 5 months on the 7th June

We will be doing the baby led weaning approach so won’t be starting his journey at 6 months

The last few days his bottles are now 7-8oz every 3 hours is this normal? I’ve been told by a weaning lady its because he is so much more active? As you can see he really isn’t overweight

Another question I use cow and gate ready milk when out (prep machine at home) they only do 7oz bottles so what do you all advise? I always worry about heat flask and powder as I don’t know how it works

Many thanks