I have had the same experience. We now have some new and proactive councillors and gradually things are changing for the better. Any Councillor can put an item on the agenda so maybe you could put 'review of standing orders' on. We have a Governance Committee, who appear to have done very little over the years but I joined and put this on the agenda. We have now adopted the 2020 Standing orders, the previous ones were from 2018, so 3 years late! We have also adopted the latest Finance regulations via the Finance Committee. I was made Chair of this committee thanks to the support of some of the new councillors.
Training should be available through NALC. I'm in Wales and our advisory body is One Voice Wales. They have a lot of training sessions covering every subject possible. NALC should have at least some that are useful, especially to new councillors. Your Chair and Clerk should be encouraging training and there should be a budget. Recent legislation changes here mean that as from the end of this year we have to publish a training schedule. I'm afraid I don't know if this applies to England.
Committees are formed at the start of the year by full Council. They should have Terms of Reference, which along with what they can do should state how often they meet. So your Clerk should be organising these meetings accordingly. I am of course presuming there's enough members for the committees to be quorate and they have items to form an agenda.