On the bright side, even with a normal credit card, your account is never billable unless you take the affirmative step to convert from Free Tier.
The free tier is very generous and what I use for personal projects and hosting.
- 2x AMD VMs each with 1GB RAM
- 4 ARM64 Cores and 24GB of RAM to divide up(or not) however you want.
- 200GB of Block Storage
- public IPv4 (and now IPv6) addresses for each VM.
- 10 TB/month egress.
Your upper limit is 4 VMs total because the minimum boot volume is 47GB, so that's the max you can subdivide the storage.