1995 Tahoe brakes

I pulled the front wheel on the Tahoe and the brake pad on the inside was wore down.

I noticed it was not braking properly the last time I drove it. the braking felt weak.

Is this a caliper issue? A slide issue? A flex line issue?

Or should I just replace The caliper, pads and flex line?

If so are there recommended parts to use?

 

Sounds like a slide issue whomever did the brakes last more than likely did not clean and grease the slides push them out grease them with some new pads I prefer Wagner brand but Brake best select from Oriely's aren't bad for the money.