If you want bonds, US equity and Foreign equity all in one single fund, then check out Vanguard's Target Date mutual funds. If you pick a target date closer to 2018, like Target Date 2025 (VTTVX), then it will have more bonds and less drops in value during a market downturn than a Target Date 2050 fund (VFIFX), which will have much more equity. Look at their glide paths into bonds when selecting one rather than just using the actual date on the fund. The buy-in amount is fairly low, $1000 in fact. This is not a get-rich-quick fund; it's a slow-and-steady-wins-the-race fund (with more contributions over the decades).
Long-term holding of Target Date funds may be better if placed into a tax-advantaged account (IRA, 401K, etc) due to capital gains distributions as the funds shift asset allocations over the years. And it grows tax-free there too.