While you should consider parsing HTML/XML I'm always dipping into Notepad++ to clean up data. You may need a few goes it this but to throw you something that may help...
https://regex101.com/r/uAPi97/1
Now the above is pretty much based on getting all the lines of...
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-01-01T10:41:18-05:00</xyzefg><**shAMount**>8000.00</afsfda;sfkj;alkfl;kaf>
...on to one line each. So switch off word wrap and check they are. You may need to find (in 'Extend mode') the...
<?
...bit and replace with...
\r<?
...as an example. Then you can (perhaps) use regex to find the entire line (you have to find the whole line), then capture the bits of interest (these are wrapped in () so they are captured). Then do a find and replace in Notepad++ but with regex mode selected.
The regex...
^.*?(\d+-\d+-\d+T\d+:\d+:\d+-\d+:\d+).*(shAMount).*?(\d+\.\d+).*$
...finds the whole line and if you replace with...
$1$2$3
...then the three bits in () from the regex are put back. So this...
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-01-01T10:41:18-05:00</xyzefg><**shAMount**>8000.00</afsfda;sfkj;alkfl;kaf>
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-02-01T10:41:18-05:00</xyzefg><**shAMount**>7000.00</afsfda;sfkj;alkfl;kaf>
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-02-01T10:41:18-05:00</xyzefg><**shAMount**>7000.00</afsfda;sfkj;alkfl;kaf>
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-02-01T10:41:18-05:00</xyzefg><**shAMount**>7000.00</afsfda;sfkj;alkfl;kaf>
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-02-01T10:41:18-05:00</xyzefg><**shAMount**>7000.00</afsfda;sfkj;alkfl;kaf>
<? xml version="1.0" of encoding="UTF-8"?><abcdefghij><**ToDateTimestamp**>2019-02-01T10:41:18-05:00</xyzefg><**shAMount**>7000.00</afsfda;sfkj;alkfl;kaf>
..sort of goes to this...
2019-01-01T10:41:18-05:00shAMount8000.00
2019-02-01T10:41:18-05:00shAMount7000.00
2019-02-01T10:41:18-05:00shAMount7000.00
2019-02-01T10:41:18-05:00shAMount7000.00
2019-02-01T10:41:18-05:00shAMount7000.00
2019-02-01T10:41:18-05:00shAMount7000.00
That may not be 100% what you want but from there you can clean it up a bit more and say, find (in Extend mode) 'shAMount' (without quotes) and replace with '\rshAMount' (without quotes). Few loops of find and replace and you may be closer to your goal.
But yes...if you do this a lot check out Python and HTML Parser - more to learn but quite powerful.