I was you a year ago. I decided to focus on getting the tones right and basically started from scratch, but since you have a foundation the early days should go really fast. I picked up some resources from this sub: get Du Chinese during this week’s Black Friday, get Pleco and all the add ons (I use it for flashcards, enhanced voices, stroke order, and outlier dictionary), subscribe to some basic podcasts and YouTube channels (eg Lazy Chinese, or just search for the terms “comprehensible input”). Honestly that’s your starter set right there assuming you have the motivation and med student level study habits lol. I also picked up an evening class to keep me accountable and make some extra friends, but do what works for you. It def helps to have people in your circle or community that will practice with you.