Yes, and you will not be the only one doing it. A large share of the people who visit Hue.Church for the first time come by themselves. You can sit anywhere, nobody will ask where the rest of your party is, and there is no seating that assumes you came with someone.
Plan Your VisitWalking into a room alone is harder than walking in with someone, and that is true of a church the same way it is true of a party or a gym. The fear is usually about the two or three minutes before it starts, when everyone else appears to already know each other and you are standing there holding a coffee.
The practical answer is to come at 10:25 rather than 10:15. Doors open at 10:15 if you want the lobby time, but arriving five minutes before the start means you walk in, sit down, and the lights go down shortly after. Plenty of people do exactly this on a first visit and it removes the part that most people dread.
Once the service starts, being alone is genuinely invisible. Nobody is doing a headcount of your row. Afterward you can leave immediately or stay, and neither reads as strange.
It is worth saying that a lot of people in the Bay Area are here without family nearby. They moved for a job, the friends came slowly if at all, and the weekends are quieter than they expected. If that is your situation, you are describing a fairly ordinary story in this room rather than an unusual one.
Coming alone once does not obligate you to anything. But if you get to a point where you want to know people rather than just attend, there is a normal path into that, and someone whose job it is to help you find it.
Quick answers
Will people ask why I came alone?
No. Nobody asks, and a lot of first time visitors come by themselves.
When should I arrive if I am coming alone?
Around 10:25 is the easiest. You walk in, sit down, and the service starts a few minutes later.
Is there anywhere to sit if I am by myself?
Anywhere you like. There is no assigned or group seating.