aws s3 cp (and sync) is well documented. The primary options are include or exclude, which lets you use filters include and exclude by folder or file type. Some examples from the documentation
aws s3 cp /tmp/foo s3://bucket/ --recursive --exclude ".git/*"
aws s3 cp /tmp/foo s3://bucket/ --recursive --include "*.txt" --exclude "*"
You may find the --recursive flag useful as well.
If you want to upload based on date I think you're going to have to write a script or code to do it. A quick Google search found this answer which is relevant.
I use CloudBerry Backup (recently renamed MSP360) for backing up my PC to S3. It has a nice GUI to select folders to back up, or optionally you can configure the backup plan with the option "Backup files modified since".
There's a free trial, after that it's $50, which is pretty cheap given the time it could save you.