Am I entitled to pay from my employer when I am absent on sick leave?

This depends on whether, as an employee, your contract of employment contains an express term entitling you to pay during sickness absence.

The written statement of particulars, which should be given to employees within 8 weeks of starting work, must specify the terms relating to sick pay, or refer to an easily accessible document which sets out those terms.

Even in the absence of an express term, there may be an implied term entitling certain grades of employee to payment during sickness.

Otherwise you would only be entitled to statutory sick pay (SSP), subject to satisfaction of the national insurance contribution rules.