I would get a website - you can get a Wix website and do it yourself for very little money and if you keep it simple it is not at all hard to make it look nice.
Having somewhere to put all the contact info, booking info and testimonials etc in one place is still a good idea, I know you can use instagram for this, but you will be cutting out a good portion of clients who will simply NOT look for or go to a business that only uses FB/Insta/Tiktok.
Do the SM, but link it together with IFTTT so one post is posted to all. Post twice a week with a nice photo and comment, it should be positive and engaging, ask a question - but DONT bullshit, its so very fake and see through now.
Do keep on top of your hashtags but otherwise, don't worry too much about SM, as long as you have a presence that is up to date, clean, bright and shows what you do, that will do.
Then have all the SM platforms point people to your website. That gives everyone a chance to find you and what you do - websites feel like 'home' and stable and dependable, whereas insta/fb/twitter feel very temporary and unstable.
Advertising wise - I would not pay for FB advertising, you will spend money reaching people who are geographically far too far away no matter how you set the settings, it isn't a good use of your money.
I would pay for decent business cards that can be given to people you meet (personal touch) and also special offers like recommend a friend or discount if they use one of your other businesses - 'third clean get 10% off your microblading or gift this card to a friend' (just have biz cards made with a blank section on the back where you can hand write a code, and keep a note of hte codes you've given out) - or whatever works for you.
Or.. focus on the other business for a bit and get some more related skills you can use to keep clients coming back to you - facial waxing, nails (whatever, I literally have no idea beyond having done some logo design for a friend who is a waxer).. any way you can keep clients coming back, is good really!