Is It OK to Do Dental Bridge by 1st Premolar and 2nd Molar As an Abutments in Case of Missing Lower 2nd Premolar and 1st Molar?

Based on your description, I feel a dental bridge is not a good option in your case. For the teeth involved I think the span of the bridge is too long. I would consider getting a consultation from someone well versed in dental implants to see if you would be a good candidate. If he/she deems you are able to have implants I would proceed with is option. Good luck.

The spanof the bridge is too long. This leaves a high chance of breaking. I would look into other treatment options.

You have to think long term success.  A bridge is putting excess force on the remaining teeth (abutments) to replace the missing teeth (pontics).  Long span Dental Bridges transfer excessive load to the abutments and will flex to a greater extent - this ultimately leads to a sooner failure.

A span of two pontics (missing teeth) will flex 8X more than a span of one pontic (one missing tooth).  I would recommend to see if you are a candidate for dental implants as a better long term solution.

Sounds like too wide a span to be properly supported by those teeth, but it all depends on a full examination, including X-rays and an evaluation of your bite. Have you considered implants instead of a bridge?