Need to resize partition by adding unallocated space from extended file system

I have the following set up, and need to simply increase the size of sda1. There is 81Gb of unallocated space, and the parts are adjacent. But, I cannot increases sda1, the option is greyed out.

Is it possible to add this unallocated space to sda1? Or do I need to format?

I am booting via a live usb.

Looks like you have an MSDOS partitioned disk and your unallocated space is inside your extended partition, so that's why you cannot just expand your sda1 into that space.

First backup any important files, changing partitions can go badly wrong with just a typo.

Next, shrink the extended partition from the left, so it does not include the unallocated space. A GUI partition tool may be easy, but using a text based tool allows you to select the sector start for the shrunken extended partition -- your choice, no matter if you don't free every last sector.

Finally, the sda1 partition now is next to unallocated space that is not within the extended partition, so may be expanded by dragging the right end to the new start of the extended partition.

Some partitioning tools will expand the enclosed filesystem when you expand on the right, some don't. Check that your filesystem size is larger, like you expected, otherwise, you will have to manually run the /sbin/resize2fs