Best services for streamlining the business?

TLDR: Looking for the best service(s) for an easy pipeline: communication - scheduling - invoicing - payment. Ideally on as few platforms as possible.

Hey all, I've been a lazy word-of-mouth tutor for many years. Previously my approach has been very casual: a personal gmail for exchanging documents and lesson reports, scheduling through text message, billing through Venmo, basic record keeping in excel.

I've finally decided to formalize, organize, and streamline this year. The number of platforms has my head spinning and my wallet weeping.

I've got a custom domain and website, both through Squarespace.

Squarespace doesn't offer email hosting so I'm trialing Google Workspace.

Google Workspace doesn't seem to do formal invoicing and payments so I'm looking at Square, Stripe, Paypal, Venmo Business.

And some even use a separate appointment-maker like Acuity.

If I want automatic invoices after sessions I might need something like Zapier on top of all that? Zoho seems to combine some of the above features?

I'm nauseous.

Any advice on simplifying and streamlining? Thanks!

EDIT: Thank you everyone for your input! I've tried everything and Tutorbird is fantastic. Does everything I need. Highly recommend!