When speaking English, I have a practice with some friends.
This is an example which I am sure many readers would say should go into the confusing words section. But as the problem is mainly created by the use of the indefinite article 'a', then I am putting it here into grammar. But there is some genuine word confusion, which I will explain later in this item.
To begin with, there is nothing wrong grammatically with the sentence above: the problem is likely to be that it is being spoken in the wrong context.
There is also a little matter with spelling, and even this differs depending on if you are using British English or American English, which can be confusing even for some native speakers.
To explain the problem: I believe that the non-native speaker is trying to explain that they like to try to use the English that they know with other similar speakers so that they can listen to each other regularly to discover how they say their words and sentences, and that the words and sentences they use that they understand are the correct grammatical structures. They are speaking it in order to be able to do it better.
They like to practise (British English) or practice (American English) their English, or they would like to have some practice/a little practice with some friends.
And there is the first piece of confusion. In British English, the verb is practise; the noun, usually uncountable, is practice. Note that subtle difference (subtle: a small change that you might not see) in spelling.
I practise my English very often (verb). I need to get some practice with my English (noun). If, of course, you want to speak colloquailly, then it would be a practice (noun, but still spelt with a 'c'). But this is not standard English so do not try it in any tests.
Now I shall confuse you further with their use for different meanings and contexts.
PRACTISE (American English: PRACTICE) - the verb, not the noun
If you practise a custom, craft, religion, you do the activities connected with them: She practised archeology. If there are regular bad things done to people: Torture being practised in some prisons. If you are a doctor or lawyer, you practise medicine or law.
PRACTICE (British English: The verb; American English, noun and verb)
In standard English a practice (both American and British English) - practice as a countable noun - is something that people do regularly: Paying people below the minimum wage is a practice that is illegal in many countries. As an uncountable noun: Lewis Hamilton was fastest in final practice for the Australian Grand Prix. It is also a word that describes the work of doctors and lawyers: controversial medical practice, and is also their place of work: The new doctor's practice is just two minutes' walk.
There are also some phrases. When something happens in practice, it is what actually happens: In practice, you should not be paying tax on this particular amount; A usual thing that is done in a particular situation: It is normal/standard/usual practice not to pass on clients' personal information; If you have not done something for a long time and are not so good now: I'm out of practice with my swimming. Finally, if you put something into practice, you do it: I'm going to put my suggestion into practice.
So there's a lot of practise... or practice... needed here. Sorry.
The words licence and license have a similar problem (and I am happy to admit that I get these mixed up myself!). Again, in the UK at least, licence is a noun (a driving licence) but license is a verb (I am licensed to sell alcohol).
In the US, both noun and verb are license.