About to graduate debt-free, how should I split savings vs investing early on?

I’m finishing my bachelor’s degree debt-free this December. I already have a June–July internship lined up that feeds into a full-time role paying around $70k/year. The internship itself will pay about $8k over two months.

Current situation:

• Monthly income (now): \~$1,000

• Monthly expenses (now): \~$500

• Current savings: \~$3,000

By graduation, I expect to have $10–15k saved. Post-graduation:

• Monthly expenses: \~$900

• That’s roughly \~20% of my take-home pay

Plan once full-time starts:

• Max employer 401(k) match (5%)

• Fully fund a Roth IRA

• After that, I’ll still have roughly $3,500/year available to save/invest

I’m very fortunate that my parents put me in a position where my expenses will stay low for the first year or two after graduation, and I want to take full advantage of that window.

Goals:

• Build a strong long-term investment base

• Save for a future mortgage

• Save for a dream car (S197 Mustang, 6-speed)

Ovc the mustang is taking the back seat but it’s still something I’d like to save towards

What kind of percentage split would you recommend between:

• Cash savings (house/car)

• Taxable investing (index funds, etc.)

• Any other buckets I should be considering early on?

Mostly looking for general allocation advice rather than exact picks. Appreciate any insight.