As soon as you stop registering for school, you SEVIS will be released and and your F1 status will be terminated.

The rule is that you have up to 60 days after you SEVIS is terminated to apply for reinstatement. However, since Nepal has TPS, the 60 days grace period does not start until the TPS ends.
There is no difference between these two options:
1. You take a break for one or two semesters, and apply for reinstatement back to F1 status.
2. You take a break until the TPS expires, you will still have 60 days after TPS expires to apply for reinstatement.

In both cases, you have to convince the USCIS that you lost the F1 status because of severe economic hardship or negligence in part of DSO. Most probably, you would apply for the first option to economic hardship. As long as you can provide enough documents during the reinstatement process, and the USCIS believes you, you will not have any issues with reinstatement.

As long as you can create strong documents to support your claim, you should be able to get reinstated to F1 visa. However, if your reinstatement gets rejected, you have to return to Nepal.