I need step by step instructions for UK Ltd

We are Ltd company and we need to submit accounts to Companies House as well as CT600 to HMRC. As far as CT600 not much problem as detailed on tax report. How can we manage to prepare accounts ? The main issue we met is when we’re making bank reconciliation there is the difference comparing to Koinly report. How you manage to make bank reconciliation correctly. Maybe we can ask some accountants over hear to have a say.