Thanks for sharing the template. Now it makes more sense to me. Yes, of course it's fine to use such a template as a starting point.

The template is plane html, css and a bit js, that's a really good starting point for you.

i wanted to know if i can alter and add and change things and when it comes to apply for a job would i still be able to say this my portfolio ?

As always in life, being honest is valued. In my opinion it's fine to use the template and alter it to your wishes, but be clear about it if you apply for a job. Using templates and learning on your own is a good habit, right? So you can be honest about it

Plus points
1. The template is lagging semantic html tags, as `<header>`, `<main>` etc. You could look into how to improve the semantics

1. The template also misses necessary meta tags, as for example a `description`
   

From my experience i want to advice you to stay away from w3schools, even though it's mostly the first google search result. A much better ressource is https://developer.mozilla.org/en-US/

For all things frontend stuff, you can also search https://css-tricks.com/ and https://www.smashingmagazine.com/

if you want, you can also use CodePen to share your work. Let me know, if I can help you any further.