As to the abbreviation ‘Esq.’ for ‘Esquire’ used by some lawyers, it has no precise significance in the United States except as sometimes applied to certain public officials, such as justices of the peace. For some reason, lawyers often add it to their surname in written address.
What’s a counsel? A solicitor would be the UK equivalent of the US attorney-at-law. Counsel usually refers to a body of legal advisers but also pertains to a single legal adviser and is a synonym for advocate, barrister, counselor, and counselor-at-law.
Lawyer is a general term for a person who gives legal advice and aid and who conducts suits in court.
In the UK, those who practice law are divided into barristers, who represent clients in open court and may appear at the bar, and solicitors, who are permitted to conduct litigation in court but not to plead cases in open court.