So, let's start with a few definitions --
$300k/year -- do you mean "bring home" aka what gets deposited into your checking account on a biweekly basis (300k/26 = $11,538.46) or do you mean $300k/year less taxes (medicare, income tax, etc) less benefits (health, LTD/STD, vision,dental) less retirement contributions (up to you)?
If you mean $300k/year before taxes/deductions -- sure. If you mean $300k/year after taxes/deductions -- you'd have to really work at it -- as that means approximately $405,000 before taxes assuming a 35% tax bracket not including deductions for benefits and retirement contributions.
Recall that there are couples who manage to put away $1million for retirement before they are 55 who are firefighters and elementary teachers that make probably less than $60k/year before taxes -- and they do this while managing to live in a nice but not elaborate home sufficient to raise a family and still enjoy life -- the kids go to college but likely need some student loans ---
the reason I bring this up is too often med students have an altered sense of reality when it comes to finances and salaries --- I worked my tail off and my wife held a full time job making $24k/year and total household income was around $42k/year before taxes, IIRC when I was transitioning into medical school --- she and the children drove the newer minivan, I had the beater Toyota standard shift pick up with no a/c that was 10 years old, our big night out was to take the children to CiCi's all you can eat pizza where we could feed everyone for less than $20 AND had enough left over to let the children to spend $0.25 a pop on a few of those gumball machine trinket dispensers. We used to have "movie night" combined with "Chipotle night" where we'd go to Family Video and let the children each pick a movie to rent and then let them help us cook while we made the fixings for make your own "Chipotle" burritos. The children wore hand me downs that were cycled through our church and we were greatful. We saved for Christmas all year (or tried to) and made sure the children had a "big" Christmas ($250/child). It was hard but we did it. I went without medical insurance for 2 years since we couldn't afford it -- doctored myself with hot toddy's and mucinex.
Yeah, I get that you've got student loans to pay back -- my monthly bill is going to be between $1800/month (25 year plan) to $3500/month (10 year plan) --- If you're in medicine for the money, you chose unwisely.