How do I speed up my MacBook Air 2015 running macOS 12.7.6?

Reasons for poor performance....could be one or more of the following:

• Not enough Free storage space (ignore the Available space value since it is misleading & is not synonymous with Free in macOS)
• Issue with third party installed software
• Hardware issue
• Just an old underpowered low end laptop that was never that speedy even when new

Run the third party app EtreCheck and post the complete report here so we can examine it for possible clues.

How to use the Add Text Feature When Posting an EtreCheck Report - Apple Community

As a point of reference, here are some Geekbench (CPU) benchmark scores.

• 2015 MacBook Air – Core i5 – 764 / 1,489
• 2015 MacBook Air – Core i7 – 1,006 / 1,969
• Plain M4 chip – 3,813 / 14,837

I took the numbers for the plain M4 chip from MacTracker's entry for the 14" M4 MacBook Pro. MacTracker does not have entries for the 13" and 15" M4 MacBook Airs yet, but their scores should be almost identical to those for the 14" M4 MacBook Pro.

Note how the single-core CPU score for the low-end M4 chip

• Beats the single-core scores for the CPUs in those old MacBook Airs by a factor of nearly 4x or 5x.
• Even beats their multi-core scores by a factor of nearly 2x.

On any sort of sustained job that can make good use of multiple cores, the beat-down is much worse. A plain M4 has a multi-core score about 10x as high as the one for one of the old Core i5s.

Inrfinrvid wrote:

My MacBook Air 2015 is so slow pls put out a update pls

If you are referring to an "update" that would let you run Ventura, Sonoma, or Sequoia, that's not going to happen. For the MacBook Air (13-inch, Early 2015), Monterey is the end of the line.

You're not being held back by a slow mechanical hard drive. None of the 2015 MacBook Airs shipped with one.

If you bought your machine with only 4 GB of RAM, lack of RAM could be easily causing performance problems. Hopefully you have 8 GB of RAM, but either way, RAM is soldered in and there is no way to expand it now except replacing the machine with one that has more.

Your CPU is either a 1.6 Ghz Intel Core™ i5-5250U or a 2.2 GHz Intel Core i7-5650U. These are mobile Intel CPUs that have only two cores. You do not have a discrete GPU – just the weak Intel integrated GPU you'd expect to see in a mobile Intel CPU launched more than ten years ago, in January 2015.

The only way to effectively speed that machine up is going to be to recycle it and buy something new.

It's 10 years old. That machine is obsolete.