can my mac back up continuously like iphone?

Time Machine's "claim to fame" is that it is the backup that gets done, because it does not ruin performance of the rest of the computer while doing its backup operations. You do not have to set aside a "Special Time" when you only do backups. When you need it, your Time machine Backup is much more likely to be there.

When using Time machine, you just set it up once and "it just works".

Initial backup will be large, and can run all afternoon, but after that you will not notice it is there, taking care of business in the background, without disturbing your important work.

How to use Time Machine to Backup or Restore your Mac:

Back up your Mac with Time Machine - Apple Support

Time machine provides near-continuous incremental backups. But rather than constantly using system resources to determine what needs to be backed up, it checks and does an incremental backup about hourly, by default.

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"On the cloud" is great for sharing photos, but is not a viable backup solution for everything you have. The stuff is not under your control, and is subject to sloppy handling, arbitrary changes in policy, theft, data loss, and bankruptcy of the company that holds it. It can easily take three days to restore it at ordinary Internet speeds.

If you do not have a recent local, disk-based backup, your computer is like a ticking Time bomb. You are only one disk failure away from losing EVERYTHING! Drives do not last forever. It is not a question of IF it will fail, only WHEN it will fail.

see these links:

How to back up your Mac - Official Apple Support

Back up your Mac with Time Machine - Apple Support